diff --git a/.gitignore b/.gitignore
index 42c4a5cb5..29f6d0f19 100644
--- a/.gitignore
+++ b/.gitignore
@@ -37,6 +37,8 @@ build-*
 bin-*
 mkqtdecl.tmp
 testtmp
+*build.macos*
+*bin.macos*
 
 # private data
 private
@@ -54,3 +56,12 @@ src/klayout.pro.user
 *.egg-info/
 build/
 dist/
+
+
+# IDEs
+.vscode
+
+
+# Macos artifacts
+*.dmg
+*.dmg.md5
diff --git a/.travis.yml b/.travis.yml
index 5917ff4cb..34ac00e1e 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -7,6 +7,37 @@ branches:
 matrix:
   include:
     # python manylinux packages
+    - name: "cp39-cp39m-manylinux1_x86_64.whl"
+      os: linux
+      sudo: true
+      language: python
+      python: '3.9'
+      services:
+        - docker
+      env:
+        - DOCKER_IMAGE="quay.io/pypa/manylinux1_x86_64"
+        - PY_VERSION="cp39-cp39"
+        - DOCKER_BUILD=true
+        - TEST_IN_HOST=true
+        - MATRIX_EVAL=""
+      cache:
+        directories:
+        - ccache
+
+    - name: "cp39-cp39m-manylinux1_i686.whl"
+      os: linux
+      sudo: true
+      services:
+        - docker
+      env:
+        - DOCKER_IMAGE="quay.io/pypa/manylinux1_i686"
+        - PY_VERSION="cp39-cp39"
+        - DOCKER_BUILD=true
+        - MATRIX_EVAL=""
+      cache:
+        directories:
+        - ccache
+
     - name: "cp38-cp38m-manylinux1_x86_64.whl"
       os: linux
       sudo: true
diff --git a/Makefile b/Makefile
index a8e1d727b..b96f80895 100644
--- a/Makefile
+++ b/Makefile
@@ -3,10 +3,10 @@
 GITCOMMIT := $(shell git rev-parse --short HEAD)
 KLAYOUT_VERSION := $(shell source version.sh && echo $$KLAYOUT_VERSION)
 ifndef PYTHON_VERSION
-    PYTHON_VERSION := B37
+    PYTHON_VERSION := HB38
 endif
 ifndef MACOS_VERSION
-	MACOS_VERSION := HighSierra
+	MACOS_VERSION := Catalina
 endif
 
 .ONESHELL:
@@ -15,11 +15,11 @@ default: help
 
 help:
 	@echo "For Mac OS only"
-	@echo "make build PYTHON_VERSION=B37"
-	@echo "make deploy PYTHON_VERSION=B37"
+	@echo "make build PYTHON_VERSION=HB38"
+	@echo "make deploy PYTHON_VERSION=HB38"
 	@echo "make test MACOS_VERSION=HighSierra"
-	@echo "Valid Mac OS Versions: [Yosemite, ElCapitan, Sierra, HighSierra]"
-	@echo "Valid Python Version: [nil, Sys, B37]"
+	@echo "Valid Mac OS Versions: [Yosemite, ElCapitan, Sierra, HighSierra, Mojave, Catalina]"
+	@echo "Valid Python Version: [nil, Sys, HB38]"
 
 build:
 	@echo "Building for Mac $(GITCOMMIT)"
@@ -29,11 +29,11 @@ build:
 deploy:
 	@echo "Deploying 4 Mac $(GITCOMMIT)"
 	./build4mac.py -p $(PYTHON_VERSION) -q Qt5Brew -y
-	
+
 test:
 	@echo "Testing 4 Mac $(GITCOMMIT)"
-	qt5.pkg.macos-$(MACOS_VERSION)-release/klayout.app/Contents/MacOS/klayout -b -r test-pylib-script.py; \
-	cd qt5.build.macos-$(MACOS_VERSION)-release; \
+	PIP_REQUIRE_VIRTUALENV="false" HW-qt5Brew.pkg.macos-$(MACOS_VERSION)-release-RsysPhb38/klayout.app/Contents/MacOS/klayout -b -r test-pylib-script.py; \
+	cd qt5Brew.build.macos-$(MACOS_VERSION)-release-RsysPhb38; \
 	ln -s klayout.app/Contents/MacOS/klayout klayout; \
 	export TESTTMP=testtmp; \
 	export TESTSRC=..; \
@@ -41,18 +41,24 @@ test:
 	./ut_runner -h || true; \
 	cd ..
 
+dmg-template:
+	mkdir -p testtemplate/klayout.app
+	./makeDMG4mac.py -p testtemplate -m -z -t klayoutDMGTemplate.dmg
+	cp -a klayoutDMGTemplate.dmg* macbuild/Resources/
+	rm -Rf testtemplate
+
 dropbox-deploy:
 	@echo "Preparing for dropbox deployment $(MACOS_VERSION) $(GITCOMMIT)"
-	mkdir -p deploy/$(MACOS_VERSION)/$(PYTHON_VERSION)/$(KLAYOUT_VERSION); \
-	pwd; \
-	ls -lah; \
-	touch build.txt; \
-	cp build.txt deploy/$(MACOS_VERSION)/$(PYTHON_VERSION)/$(KLAYOUT_VERSION)/qt5.pkg.macos-$(MACOS_VERSION)-$(PYTHON_VERSION)-release-$(KLAYOUT_VERSION)-$(GITCOMMIT).log.txt; \
-	hdiutil convert macbuild/Resources/klayoutDMGTemplate.dmg -format UDRW -o work-KLayout.dmg; \
-	hdiutil resize -size 500m work-KLayout.dmg; \
-	hdiutil attach work-KLayout.dmg -readwrite -noverify -quiet -mountpoint tempKLayout -noautoopen; \
-	cp -a qt5.pkg.macos-$(MACOS_VERSION)-release/ tempKLayout/; \
-	hdiutil detach tempKLayout; \
-	hdiutil convert work-KLayout.dmg -format UDZO -imagekey zlib-level=9 -o deploy/$(MACOS_VERSION)/$(PYTHON_VERSION)/$(KLAYOUT_VERSION)/qt5.pkg.macos-$(MACOS_VERSION)-$(PYTHON_VERSION)-release-$(KLAYOUT_VERSION)-$(GITCOMMIT).dmg; \
-	md5 -q deploy/$(MACOS_VERSION)/$(PYTHON_VERSION)/$(KLAYOUT_VERSION)/qt5.pkg.macos-$(MACOS_VERSION)-$(PYTHON_VERSION)-release-$(KLAYOUT_VERSION)-$(GITCOMMIT).dmg > deploy/$(MACOS_VERSION)/$(PYTHON_VERSION)/$(KLAYOUT_VERSION)/qt5.pkg.macos-$(MACOS_VERSION)-$(PYTHON_VERSION)-release-$(KLAYOUT_VERSION)-$(GITCOMMIT).dmg.md5; \
+	mkdir -p deploy/$(MACOS_VERSION)/$(PYTHON_VERSION)/$(KLAYOUT_VERSION)
+	pwd
+	ls -lah
+	touch build.txt
+	cp build.txt deploy/$(MACOS_VERSION)/$(PYTHON_VERSION)/$(KLAYOUT_VERSION)/qt5.pkg.macos-$(MACOS_VERSION)-$(PYTHON_VERSION)-release-$(KLAYOUT_VERSION)-$(GITCOMMIT).log.txt
+	hdiutil convert macbuild/Resources/klayoutDMGTemplate.dmg -ov -format UDRW -o work-KLayout.dmg
+	hdiutil resize -size 500m work-KLayout.dmg
+	hdiutil attach -readwrite -noverify -quiet -mountpoint tempKLayout -noautoopen work-KLayout.dmg
+	cp -a HW-qt5Brew.pkg.macos-$(MACOS_VERSION)-release-RsysPhb38/ tempKLayout/
+	hdiutil detach tempKLayout
+	hdiutil convert work-KLayout.dmg -ov -format UDZO -imagekey zlib-level=9 -o deploy/$(MACOS_VERSION)/$(PYTHON_VERSION)/$(KLAYOUT_VERSION)/qt5.pkg.macos-$(MACOS_VERSION)-$(PYTHON_VERSION)-release-$(KLAYOUT_VERSION)-$(GITCOMMIT).dmg
+	md5 -q deploy/$(MACOS_VERSION)/$(PYTHON_VERSION)/$(KLAYOUT_VERSION)/qt5.pkg.macos-$(MACOS_VERSION)-$(PYTHON_VERSION)-release-$(KLAYOUT_VERSION)-$(GITCOMMIT).dmg > deploy/$(MACOS_VERSION)/$(PYTHON_VERSION)/$(KLAYOUT_VERSION)/qt5.pkg.macos-$(MACOS_VERSION)-$(PYTHON_VERSION)-release-$(KLAYOUT_VERSION)-$(GITCOMMIT).dmg.md5
 	rm work-KLayout.dmg
diff --git a/build.sh b/build.sh
index 6c6150e8f..676d8aa99 100755
--- a/build.sh
+++ b/build.sh
@@ -532,6 +532,11 @@ if [ "$BIN" = "" ]; then
   BIN=$CURR_DIR/bin-$CONFIG
 fi
 
+if [ "$QMAKE_CCACHE" = 1 ]; then
+  echo "    Compilation caching is activated."
+else
+  echo "    Compilation caching is deactivated!"
+fi
 echo "    Installation target: $BIN"
 echo "    Build directory: $BUILD"
 
diff --git a/macbuild/.gitignore b/macbuild/.gitignore
index 0d20b6487..4081080e3 100644
--- a/macbuild/.gitignore
+++ b/macbuild/.gitignore
@@ -1 +1,2 @@
 *.pyc
+KLayoutDMG.applescript
diff --git a/macbuild/ReadMe.md b/macbuild/ReadMe.md
index 4f87e9616..09344755b 100644
--- a/macbuild/ReadMe.md
+++ b/macbuild/ReadMe.md
@@ -1,4 +1,4 @@
-Relevant KLayout version: 0.26.5
+Relevant KLayout version: 0.26.7
 
 # 1. Introduction
 This directory **`macbuild`** contains different files required for building KLayout (http://www.klayout.de/) version 0.26.1 or later for different 64-bit Mac OSXs including:
@@ -72,16 +72,16 @@ $ [python] ./build4mac.py
                         :   MP26: use Ruby 2.6 from MacPorts                             |
                         :   HB27: use Ruby 2.7 from Homebrew                             |
                         :   Ana3: use Ruby 2.5 from Anaconda3                            |
-   [-p|--python <type>] : case-insensitive type=['nil', 'Sys', 'MP37', 'HB37', 'Ana3']   | sys
+   [-p|--python <type>] : case-insensitive type=['nil', 'Sys', 'MP38', 'HB38', 'Ana3']   | sys
                         :    nil: don't bind Python                                      |
                         :    Sys: use OS-bundled Python 2.7 [ElCapitan -- Catalina]      |
-                        :   MP37: use Python 3.7 from MacPorts                           |
-                        :   HB37: use Python 3.7 from Homebrew                           |
-                        :   Ana3: use Python 3.7 from Anaconda3                          |
+                        :   MP38: use Python 3.8 from MacPorts                           |
+                        :   HB38: use Python 3.8 from Homebrew                           |
+                        :   Ana3: use Python 3.8 from Anaconda3                          |
    [-n|--noqtbinding]   : don't create Qt bindings for ruby scripts                      | disabled
    [-m|--make <option>] : option passed to 'make'                                        | '-j4'
    [-d|--debug]         : enable debug mode build                                        | disabled
-   [-c|--checkcom]      : check command-line and exit without building                   | disabled
+   [-c|--checkcom]      : check command line and exit without building                   | disabled
    [-y|--deploy]        : deploy executables and dylibs including Qt's Frameworks        | disabled
    [-Y|--DEPLOY]        : deploy executables and dylibs for those who built KLayout      | disabled
                         : from the source code and use the tools in the same machine     |
@@ -126,64 +126,64 @@ Then the directory name will be **`LW-qt5MP.pkg.macos-Catalina-release-RsysPsys`
 
 #### If you build KLayout from the source code AND use it on the same machine, "-Y" option is highly recommended. ####
 
-### 6B. Fully MacPorts-flavored build with MacPorts Ruby 2.6 and MacPorts Python 3.7
+### 6B. Fully MacPorts-flavored build with MacPorts Ruby 2.6 and MacPorts Python 3.8
 ```
 $ cd /where/'build.sh'/exists
-$ ./build4mac.py -q qt5macports -r mp26 -p mp37
+$ ./build4mac.py -q qt5macports -r mp26 -p mp38
 ```
 2. Confirm successful build (it will take about one hour depending on your machine spec).
 3. Run **`build4mac.py`** again with the same options used in 1. PLUS "-Y" to deploy executables and libraries under **`klayout.app`** bundle.<br>
    The buddy command-line tools (strm*) will also be deployed in this step.
 ```
-$ ./build4mac.py -q qt5macports -r mp26 -p mp37 -Y
+$ ./build4mac.py -q qt5macports -r mp26 -p mp38 -Y
 ```
   The application bundle **`klayout.app`** is located under:<br>
-  **`LW-qt5MP.pkg.macos-Catalina-release-Rmp26Pmp37`** directory, where
+  **`LW-qt5MP.pkg.macos-Catalina-release-Rmp26Pmp38`** directory, where
 * "LW-"        means that this is a lightweight package.
 * "qt5MP"      means that Qt5 from MacPorts is used.
-* "Rmp26Pmp37" means that Ruby is 2.6 from MacPorts; Python is 3.7 from MacPorts.
+* "Rmp26Pmp38" means that Ruby is 2.6 from MacPorts; Python is 3.8 from MacPorts.
 4. Copy/move the generated application bundle **`klayout.app`** to your **`/Applications`** directory for installation.
 
-### 6C. Fully Homebrew-flavored build with Homebrew Ruby 2.7 and Homebrew Python 3.7
+### 6C. Fully Homebrew-flavored build with Homebrew Ruby 2.7 and Homebrew Python 3.8
 ```
 $ cd /where/'build.sh'/exists
-$ ./build4mac.py -q qt5brew -r hb27 -p hb37
+$ ./build4mac.py -q qt5brew -r hb27 -p hb38
 ```
 2. Confirm successful build (it will take about one hour depending on your machine spec).
 3. Run **`build4mac.py`** again with the same options used in 1. PLUS "-Y" to deploy executables and libraries under **`klayout.app`** bundle.<br>
    The buddy command-line tools (strm*) will also be deployed in this step.
 ```
-$ ./build4mac.py -q qt5brew -r hb27 -p hb37 -Y
+$ ./build4mac.py -q qt5brew -r hb27 -p hb38 -Y
 ```
   The application bundle **`klayout.app`** is located under:<br>
-  **`LW-qt5Brew.pkg.macos-Catalina-release-Rhb27Phb37`** directory, where
+  **`LW-qt5Brew.pkg.macos-Catalina-release-Rhb27Phb38`** directory, where
 * "LW-"        means that this is a lightweight package.
 * "qt5Brew"    means that Qt5 from Homebrew is used.
-* "Rhb27Phb37" means that Ruby is 2.7 from Homebrew; Python is 3.7 from Homebrew.
+* "Rhb27Phb38" means that Ruby is 2.7 from Homebrew; Python is 3.8 from Homebrew.
 4. Copy/move the generated application bundle **`klayout.app`** to your **`/Applications`** directory for installation.
 
-### 6D. Partially Homebrew-flavored build with System Ruby and Homebrew Python 3.7
+### 6D. Partially Homebrew-flavored build with System Ruby and Homebrew Python 3.8
 ```
 $ cd /where/'build.sh'/exists
-$ ./build4mac.py -q qt5brew -r sys -p hb37
+$ ./build4mac.py -q qt5brew -r sys -p hb38
 ```
 2. Confirm successful build (it will take about one hour depending on your machine spec).
 3. Run **`build4mac.py`** again with the same options used in 1. PLUS "-y" to deploy executables and libraries (including Qt's frameworks and Python frameworks) under **`klayout.app`** bundle.<br>
    The buddy command-line tools (strm*) will also be deployed in this step.
 ```
-$ ./build4mac.py -q qt5brew -r sys -p hb37 -y
+$ ./build4mac.py -q qt5brew -r sys -p hb38 -y
 ```
   The application bundle **`klayout.app`** is located under:<br>
-  **`HW-qt5Brew.pkg.macos-Catalina-release-RsysPhb37`** directory, where
+  **`HW-qt5Brew.pkg.macos-Catalina-release-RsysPhb38`** directory, where
 * "HW-"        means that this is a heavyweight package because both Qt5 and Python are deployed.
 * "qt5Brew"    means that Qt5 from Homebrew is used.
-* "RsysPhb37"  means that Ruby is OS-bundled; Python is 3.7 from Homebrew.
+* "RsysPhb38"  means that Ruby is OS-bundled; Python is 3.8 from Homebrew.
 4. Copy/move the generated application bundle **`klayout.app`** to your **`/Applications`** directory for installation.
 ### Important ###
 So far, deployment of Homebrew Ruby is not supported. <br>
 Therefore, if you intend to use "-y" option, you need to use "-r sys" for building.
 
-### 6E. Fully Anaconda3-flavored build with Anaconda3 Ruby 2.5 and Anaconda3 Python 3.7
+### 6E. Fully Anaconda3-flavored build with Anaconda3 Ruby 2.5 and Anaconda3 Python 3.8
 ```
 $ cd /where/'build.sh'/exists
 $ ./build4mac.py -q qt5ana3 -r ana3 -p ana3
@@ -198,7 +198,7 @@ $ ./build4mac.py -q qt5ana3 -r ana3 -p ana3 -Y
   **`LW-qt5Ana3.pkg.macos-Catalina-release-Rana3Pana3`** directory, where
 * "LW-"        means that this is a lightweight package.
 * "qt5Ana3"    means that Qt5 from Anaconda3 is used.
-* "Rana3Pana3" means that Ruby (2.5) is from Anaconda3; Python (3.7) is from Anaconda3.
+* "Rana3Pana3" means that Ruby (2.5) is from Anaconda3; Python (3.8) is from Anaconda3.
 4. Copy/move the generated application bundle **`klayout.app`** to your **`/Applications`** directory for installation.
 5. You may have to set `PYTHONHOME` environment variable like:
 ```
diff --git a/macbuild/Resources/klayoutDMGTemplate.dmg b/macbuild/Resources/klayoutDMGTemplate.dmg
index 8ad28f4ad..65ca57755 100644
Binary files a/macbuild/Resources/klayoutDMGTemplate.dmg and b/macbuild/Resources/klayoutDMGTemplate.dmg differ
diff --git a/macbuild/Resources/script-bundle-A.zip b/macbuild/Resources/script-bundle-A.zip
index 990050af7..eda075de5 100644
Binary files a/macbuild/Resources/script-bundle-A.zip and b/macbuild/Resources/script-bundle-A.zip differ
diff --git a/macbuild/Resources/script-bundle-B.zip b/macbuild/Resources/script-bundle-B.zip
index 253e8ae6b..0a8dfe893 100644
Binary files a/macbuild/Resources/script-bundle-B.zip and b/macbuild/Resources/script-bundle-B.zip differ
diff --git a/macbuild/Resources/script-bundle-P.zip b/macbuild/Resources/script-bundle-P.zip
index d8b11fa06..afdc90968 100644
Binary files a/macbuild/Resources/script-bundle-P.zip and b/macbuild/Resources/script-bundle-P.zip differ
diff --git a/macbuild/Resources/template-KLayoutDMG.applescript b/macbuild/Resources/template-KLayoutDMG.applescript
index 78d5b00d7..c27b6c10c 100644
--- a/macbuild/Resources/template-KLayoutDMG.applescript
+++ b/macbuild/Resources/template-KLayoutDMG.applescript
@@ -26,6 +26,12 @@
 -------------------------------------------------------------------------------------------------
 on run (volumeName) -- most likely, the volume name is "KLayout"
     tell application "Finder"
+        repeat 20 times
+            if (exists (disk (volumeName as string))) then
+                exit repeat
+            end if
+            delay 1
+        end repeat
         tell disk (volumeName as string)
             -- [1] Open the volume
             open
diff --git a/macbuild/build4mac.py b/macbuild/build4mac.py
index d5bc8732a..9657b9f94 100755
--- a/macbuild/build4mac.py
+++ b/macbuild/build4mac.py
@@ -27,550 +27,661 @@ from build4mac_util import *
 #-------------------------------------------------------------------------------
 ## To set global variables including present directory and platform info.
 #-------------------------------------------------------------------------------
-def SetGlobals():
-  global ProjectDir         # project directory where "build.sh" exists
-  global Usage              # string on usage
-  global BuildBash          # the main build Bash script
-  global Platform           # platform
-  global ModuleQt           # Qt module to be used
-  global ModuleRuby         # Ruby module to be used
-  global ModulePython       # Python module to be used
-  global NonOSStdLang       # True if non-OS-standard language is chosen
-  global NoQtBindings       # True if not creating Qt bindings for Ruby scripts
-  global MakeOptions        # options passed to `make`
-  global DebugMode          # True if debug mode build
-  global CheckComOnly       # True if only for checking the command line parameters to "build.sh"
-  global DeploymentF        # True if fully (including Qt's Frameworks) deploy the binaries for bundles
-  global DeploymentP        # True if partially deploy the binaries excluding Qt's Frameworks
-  global PackagePrefix      # the package prefix: 'ST-', 'LW-', 'HW-', or 'EX-'
-  global DeployVerbose      # -verbose=<0-3> level passed to 'macdeployqt' tool
-  global Version            # KLayout's version
-  global ModuleSet          # (Qt, Ruby, Python)-tuple
-  # auxiliary variables on platform
-  global System             # 6-tuple from platform.uname()
-  global Node               # - do -
-  global Release            # - do -
-  global Version            # - do -
-  global Machine            # - do -
-  global Processor          # - do -
-  global Bit                # machine bit-size
+def get_default_config():
+    """
+    Returns a dictionary containing the default configuration for the macOS build.
+    """
+    # global ProjectDir         # project directory where "build.sh" exists
+    # global Usage              # string on usage
+    # global BuildBash          # the main build Bash script
+    # global Platform           # platform
+    # global ModuleQt           # Qt module to be used
+    # global ModuleRuby         # Ruby module to be used
+    # global ModulePython       # Python module to be used
+    # global NonOSStdLang       # True if non-OS-standard language is chosen
+    # global NoQtBindings       # True if not creating Qt bindings for Ruby scripts
+    # global MakeOptions        # options passed to `make`
+    # global DebugMode          # True if debug mode build
+    # global CheckComOnly       # True if only for checking the command line parameters to "build.sh"
+    # global DeploymentF        # True if fully (including Qt's Frameworks) deploy the binaries for bundles
+    # global DeploymentP        # True if partially deploy the binaries excluding Qt's Frameworks
+    # global PackagePrefix      # the package prefix: 'ST-', 'LW-', 'HW-', or 'EX-'
+    # global DeployVerbose      # -verbose=<0-3> level passed to 'macdeployqt' tool
+    # global Version            # KLayout's version
+    # global ModuleSet          # (Qt, Ruby, Python)-tuple
+    # # auxiliary variables on platform
+    # global System             # 6-tuple from platform.uname()
+    # global Node               # - do -
+    # global Release            # - do -
+    # global Version            # - do -
+    # global Machine            # - do -
+    # global Processor          # - do -
 
-  Usage  = "\n"
-  Usage += "---------------------------------------------------------------------------------------------------------\n"
-  Usage += "<< Usage of 'build4mac.py' >>\n"
-  Usage += "       for building KLayout 0.26.1 or later on different Apple Mac OSX platforms.\n"
-  Usage += "\n"
-  Usage += "$ [python] ./build4mac.py \n"
-  Usage += "   option & argument    : descriptions (refer to 'macbuild/build4mac_env.py' for details)| default value\n"
-  Usage += "   --------------------------------------------------------------------------------------+---------------\n"
-  Usage += "   [-q|--qt <type>]     : case-insensitive type=['Qt5MacPorts', 'Qt5Brew', 'Qt5Ana3']    | qt5macports \n"
-  Usage += "                        :   Qt5MacPorts: use Qt5 from MacPorts                           | \n"
-  Usage += "                        :       Qt5Brew: use Qt5 from Homebrew                           | \n"
-  Usage += "                        :       Qt5Ana3: use Qt5 from Anaconda3                          | \n"
-  Usage += "   [-r|--ruby <type>]   : case-insensitive type=['nil', 'Sys', 'MP26', 'HB27', 'Ana3']   | sys \n"
-  Usage += "                        :    nil: don't bind Ruby                                        | \n"
-  Usage += "                        :    Sys: use OS-bundled Ruby [2.0 - 2.6] depending on OS        | \n"
-  Usage += "                        :   MP26: use Ruby 2.6 from MacPorts                             | \n"
-  Usage += "                        :   HB27: use Ruby 2.7 from Homebrew                             | \n"
-  Usage += "                        :   Ana3: use Ruby 2.5 from Anaconda3                            | \n"
-  Usage += "   [-p|--python <type>] : case-insensitive type=['nil', 'Sys', 'MP37', 'HB37', 'Ana3']   | sys \n"
-  Usage += "                        :    nil: don't bind Python                                      | \n"
-  Usage += "                        :    Sys: use OS-bundled Python 2.7 [ElCapitan -- Catalina]      | \n"
-  Usage += "                        :   MP37: use Python 3.7 from MacPorts                           | \n"
-  Usage += "                        :   HB37: use Python 3.7 from Homebrew                           | \n"
-  Usage += "                        :   Ana3: use Python 3.7 from Anaconda3                          | \n"
-  Usage += "   [-n|--noqtbinding]   : don't create Qt bindings for ruby scripts                      | disabled \n"
-  Usage += "   [-m|--make <option>] : option passed to 'make'                                        | '-j4' \n"
-  Usage += "   [-d|--debug]         : enable debug mode build                                        | disabled \n"
-  Usage += "   [-c|--checkcom]      : check command line and exit without building                   | disabled \n"
-  Usage += "   [-y|--deploy]        : deploy executables and dylibs including Qt's Frameworks        | disabled \n"
-  Usage += "   [-Y|--DEPLOY]        : deploy executables and dylibs for those who built KLayout      | disabled \n"
-  Usage += "                        : from the source code and use the tools in the same machine     | \n"
-  Usage += "                        : ! After confirmation of successful build of 'klayout.app',     | \n"
-  Usage += "                        :   rerun this script with BOTH:                                 | \n"
-  Usage += "                        :     1) the same options used for building AND                  | \n"
-  Usage += "                        :     2) <-y|--deploy> OR <-Y|--DEPLOY>                          | \n"
-  Usage += "                        :   optionally with [-v|--verbose <0-3>]                         | \n"
-  Usage += "   [-v|--verbose <0-3>] : verbose level of `macdeployqt' (effective with -y only)        | 1 \n"
-  Usage += "                        : 0 = no output, 1 = error/warning (default),                    | \n"
-  Usage += "                        : 2 = normal,    3 = debug                                       | \n"
-  Usage += "   [-?|--?]             : print this usage and exit                                      | disabled \n"
-  Usage += "-----------------------------------------------------------------------------------------+---------------\n"
+    Usage  = "\n"
+    Usage += "---------------------------------------------------------------------------------------------------------\n"
+    Usage += "<< Usage of 'build4mac.py' >>\n"
+    Usage += "       for building KLayout 0.26.1 or later on different Apple Mac OSX platforms.\n"
+    Usage += "\n"
+    Usage += "$ [python] ./build4mac.py \n"
+    Usage += "   option & argument    : descriptions (refer to 'macbuild/build4mac_env.py' for details)| default value\n"
+    Usage += "   --------------------------------------------------------------------------------------+---------------\n"
+    Usage += "   [-q|--qt <type>]     : case-insensitive type=['Qt5MacPorts', 'Qt5Brew', 'Qt5Ana3']    | qt5macports \n"
+    Usage += "                        :   Qt5MacPorts: use Qt5 from MacPorts                           | \n"
+    Usage += "                        :       Qt5Brew: use Qt5 from Homebrew                           | \n"
+    Usage += "                        :       Qt5Ana3: use Qt5 from Anaconda3                          | \n"
+    Usage += "   [-r|--ruby <type>]   : case-insensitive type=['nil', 'Sys', 'MP26', 'HB27', 'Ana3']   | sys \n"
+    Usage += "                        :    nil: don't bind Ruby                                        | \n"
+    Usage += "                        :    Sys: use OS-bundled Ruby [2.0 - 2.6] depending on OS        | \n"
+    Usage += "                        :   MP26: use Ruby 2.6 from MacPorts                             | \n"
+    Usage += "                        :   HB27: use Ruby 2.7 from Homebrew                             | \n"
+    Usage += "                        :   Ana3: use Ruby 2.5 from Anaconda3                            | \n"
+    Usage += "   [-p|--python <type>] : case-insensitive type=['nil', 'Sys', 'MP38', 'HB38', 'Ana3']   | sys \n"
+    Usage += "                        :    nil: don't bind Python                                      | \n"
+    Usage += "                        :    Sys: use OS-bundled Python 2.7 [ElCapitan -- Catalina]      | \n"
+    Usage += "                        :   MP38: use Python 3.8 from MacPorts                           | \n"
+    Usage += "                        :   HB38: use Python 3.8 from Homebrew                           | \n"
+    Usage += "                        :   Ana3: use Python 3.7 from Anaconda3                          | \n"
+    Usage += "   [-n|--noqtbinding]   : don't create Qt bindings for ruby scripts                      | disabled \n"
+    Usage += "   [-m|--make <option>] : option passed to 'make'                                        | '-j4' \n"
+    Usage += "   [-d|--debug]         : enable debug mode build                                        | disabled \n"
+    Usage += "   [-c|--checkcom]      : check command line and exit without building                   | disabled \n"
+    Usage += "   [-y|--deploy]        : deploy executables and dylibs including Qt's Frameworks        | disabled \n"
+    Usage += "   [-Y|--DEPLOY]        : deploy executables and dylibs for those who built KLayout      | disabled \n"
+    Usage += "                        : from the source code and use the tools in the same machine     | \n"
+    Usage += "                        : ! After confirmation of successful build of 'klayout.app',     | \n"
+    Usage += "                        :   rerun this script with BOTH:                                 | \n"
+    Usage += "                        :     1) the same options used for building AND                  | \n"
+    Usage += "                        :     2) <-y|--deploy> OR <-Y|--DEPLOY>                          | \n"
+    Usage += "                        :   optionally with [-v|--verbose <0-3>]                         | \n"
+    Usage += "   [-v|--verbose <0-3>] : verbose level of `macdeployqt' (effective with -y only)        | 1 \n"
+    Usage += "                        : 0 = no output, 1 = error/warning (default),                    | \n"
+    Usage += "                        : 2 = normal,    3 = debug                                       | \n"
+    Usage += "   [-?|--?]             : print this usage and exit                                      | disabled \n"
+    Usage += "-----------------------------------------------------------------------------------------+---------------\n"
 
-  ProjectDir = os.getcwd()
-  BuildBash  = "./build.sh"
-  (System, Node, Release, Version, Machine, Processor) = platform.uname()
+    ProjectDir = os.getcwd()
+    BuildBash  = "./build.sh"
+    (System, Node, Release, MacVersion, Machine, Processor) = platform.uname()
 
-  if not System == "Darwin":
-    print("")
-    print( "!!! Sorry. Your system <%s> looks like non-Mac" % System, file=sys.stderr )
-    print(Usage)
-    sys.exit(1)
+    if not System == "Darwin":
+        print("")
+        print( "!!! Sorry. Your system <%s> looks like non-Mac" % System, file=sys.stderr )
+        print(Usage)
+        sys.exit(1)
 
-  release = int( Release.split(".")[0] ) # take the first of ['19', '0', '0']
-  if   release == 19:
-    Platform = "Catalina"
-  elif release == 18:
-    Platform = "Mojave"
-  elif release == 17:
-    Platform = "HighSierra"
-  elif release == 16:
-    Platform = "Sierra"
-  elif release == 15:
-    Platform = "ElCapitan"
-  else:
-    Platform = ""
-    print("")
-    print( "!!! Sorry. Unsupported major OS release <%d>" % release, file=sys.stderr )
-    print(Usage)
-    sys.exit(1)
+    release = int( Release.split(".")[0] ) # take the first of ['19', '0', '0']
+    if   release == 20:
+        Platform = "BigSur"
+    elif release == 19:
+        Platform = "Catalina"
+    elif release == 18:
+        Platform = "Mojave"
+    elif release == 17:
+        Platform = "HighSierra"
+    elif release == 16:
+        Platform = "Sierra"
+    elif release == 15:
+        Platform = "ElCapitan"
+    else:
+        Platform = ""
+        print("")
+        print( "!!! Sorry. Unsupported major OS release <%d>" % release, file=sys.stderr )
+        print(Usage)
+        sys.exit(1)
 
-  if not Machine == "x86_64":
-    print("")
-    print( "!!! Sorry. Only x86_64 architecture machine is supported but found <%s>" % Machine, file=sys.stderr )
-    print(Usage)
-    sys.exit(1)
+    if not Machine == "x86_64":
+        print("")
+        print( "!!! Sorry. Only x86_64 architecture machine is supported but found <%s>" % Machine, file=sys.stderr )
+        print(Usage)
+        sys.exit(1)
 
-  # Set the default modules
-  ModuleQt = "Qt5MacPorts"
-  if   Platform == "Catalina":
-    ModuleRuby   = "RubyCatalina"
-    ModulePython = "PythonCatalina"
-  elif Platform == "Mojave":
-    ModuleRuby   = "RubyMojave"
-    ModulePython = "PythonMojave"
-  elif Platform == "HighSierra":
-    ModuleRuby   = "RubyHighSierra"
-    ModulePython = "PythonHighSierra"
-  elif Platform == "Sierra":
-    ModuleRuby   = "RubySierra"
-    ModulePython = "PythonSierra"
-  elif Platform == "ElCapitan":
-    ModuleRuby   = "RubyElCapitan"
-    ModulePython = "PythonElCapitan"
-  else:
-    ModuleRuby   = "nil"
-    ModulePython = "nil"
+    # Set the default modules
+    ModuleQt = "Qt5MacPorts"
+    if   Platform == "Catalina":
+        ModuleRuby   = "RubyCatalina"
+        ModulePython = "PythonCatalina"
+    elif Platform == "Mojave":
+        ModuleRuby   = "RubyMojave"
+        ModulePython = "PythonMojave"
+    elif Platform == "HighSierra":
+        ModuleRuby   = "RubyHighSierra"
+        ModulePython = "PythonHighSierra"
+    elif Platform == "Sierra":
+        ModuleRuby   = "RubySierra"
+        ModulePython = "PythonSierra"
+    elif Platform == "ElCapitan":
+        ModuleRuby   = "RubyElCapitan"
+        ModulePython = "PythonElCapitan"
+    else:
+        ModuleRuby   = "nil"
+        ModulePython = "nil"
 
-  NonOSStdLang  = False
-  NoQtBindings  = False
-  MakeOptions   = "-j4"
-  DebugMode     = False
-  CheckComOnly  = False
-  DeploymentF   = False
-  DeploymentP   = False
-  PackagePrefix = ""
-  DeployVerbose = 1
-  Version       = GetKLayoutVersionFrom( "./version.sh" )
-  ModuleSet     = ( 'qt5MP', 'Sys', 'Sys' )
+    NonOSStdLang  = False
+    NoQtBindings  = False
+    MakeOptions   = "-j4"
+    DebugMode     = False
+    CheckComOnly  = False
+    DeploymentF   = False
+    DeploymentP   = False
+    PackagePrefix = ""
+    DeployVerbose = 1
+    Version       = GetKLayoutVersionFrom( "./version.sh" )
+    ModuleSet     = ( 'qt5MP', 'Sys', 'Sys' )
+
+    config = dict()
+
+    config['ProjectDir'] = ProjectDir             # project directory where "build.sh" exists
+    config['Usage'] = Usage                       # string on usage
+    config['BuildBash'] = BuildBash               # the main build Bash script
+    config['Platform'] = Platform                 # platform
+    config['ModuleQt'] = ModuleQt                 # Qt module to be used
+    config['ModuleRuby'] = ModuleRuby             # Ruby module to be used
+    config['ModulePython'] = ModulePython         # Python module to be used
+    config['NonOSStdLang'] = NonOSStdLang         # True if non-OS-standard language is chosen
+    config['NoQtBindings'] = NoQtBindings         # True if not creating Qt bindings for Ruby scripts
+    config['MakeOptions'] = MakeOptions           # options passed to `make`
+    config['DebugMode'] = DebugMode               # True if debug mode build
+    config['CheckComOnly'] = CheckComOnly         # True if only for checking the command line parameters to "build.sh"
+    config['DeploymentF'] = DeploymentF           # True if fully (including Qt's Frameworks) deploy the binaries for bundles
+    config['DeploymentP'] = DeploymentP           # True if partially deploy the binaries excluding Qt's Frameworks
+    config['PackagePrefix'] = PackagePrefix       # the package prefix: 'ST-', 'LW-', 'HW-', or 'EX-'
+    config['DeployVerbose'] = DeployVerbose       # -verbose=<0-3> level passed to 'macdeployqt' tool
+    config['Version'] = Version                   # KLayout's version
+    config['ModuleSet'] = ModuleSet               # (Qt, Ruby, Python)-tuple
+    # auxiliary variables on platform
+    config['System'] = System                     # 6-tuple from platform.uname()
+    config['Node'] = Node                         # - do -
+    config['Release'] = Release                   # - do -
+    config['MacVersion'] = MacVersion             # - do -
+    config['Machine'] = Machine                   # - do -
+    config['Processor'] = Processor               # - do -
+    return config
 
 #------------------------------------------------------------------------------
 ## To get command line parameters
 #------------------------------------------------------------------------------
-def ParseCommandLineArguments():
-  global Usage
-  global Platform
-  global ModuleQt
-  global ModuleRuby
-  global ModulePython
-  global NonOSStdLang
-  global NoQtBindings
-  global MakeOptions
-  global DebugMode
-  global CheckComOnly
-  global DeploymentF
-  global DeploymentP
-  global PackagePrefix
-  global DeployVerbose
-  global ModuleSet
+def parse_cli_args(config):
+    Usage         = config['Usage']          #
+    Platform      = config['Platform']       #
+    Release       = config['Release']        #
+    Machine       = config['Machine']        #
+    ModuleQt      = config['ModuleQt']       #
+    ModuleRuby    = config['ModuleRuby']     #
+    ModulePython  = config['ModulePython']   #
+    NonOSStdLang  = config['NonOSStdLang']   #
+    NoQtBindings  = config['NoQtBindings']   #
+    MakeOptions   = config['MakeOptions']    #
+    DebugMode     = config['DebugMode']      #
+    CheckComOnly  = config['CheckComOnly']   #
+    DeploymentF   = config['DeploymentF']    #
+    DeploymentP   = config['DeploymentP']    #
+    PackagePrefix = config['PackagePrefix']  #
+    DeployVerbose = config['DeployVerbose']  #
+    ModuleSet     = config['ModuleSet']      #
 
-  p = optparse.OptionParser( usage=Usage )
-  p.add_option( '-q', '--qt',
-                dest='type_qt',
-                help="Qt type=['Qt5MacPorts', 'Qt5Brew', 'Qt5Ana3']" )
+    p = optparse.OptionParser( usage=Usage )
+    p.add_option( '-q', '--qt',
+                                dest='type_qt',
+                                help="Qt type=['Qt5MacPorts', 'Qt5Brew', 'Qt5Ana3']" )
 
-  p.add_option( '-r', '--ruby',
-                dest='type_ruby',
-                help="Ruby type=['nil', 'Sys', 'MP26', 'HB27', 'Ana3']" )
+    p.add_option( '-r', '--ruby',
+                                dest='type_ruby',
+                                help="Ruby type=['nil', 'Sys', 'MP26', 'HB27', 'Ana3']" )
 
-  p.add_option( '-p', '--python',
-                dest='type_python',
-                help="Python type=['nil', 'Sys', 'MP37', 'HB37', 'Ana3']" )
+    p.add_option( '-p', '--python',
+                                dest='type_python',
+                                help="Python type=['nil', 'Sys', 'MP38', 'HB38', 'Ana3']" )
 
-  p.add_option( '-n', '--noqtbinding',
-                action='store_true',
-                dest='no_qt_binding',
-                default=False,
-                help="do not create Qt bindings for Ruby scripts" )
+    p.add_option( '-n', '--noqtbinding',
+                                action='store_true',
+                                dest='no_qt_binding',
+                                default=False,
+                                help="do not create Qt bindings for Ruby scripts" )
 
-  p.add_option( '-m', '--make',
-                dest='make_option',
-                help="options passed to `make`" )
+    p.add_option( '-m', '--make',
+                                dest='make_option',
+                                help="options passed to `make`" )
 
-  p.add_option( '-d', '--debug',
-                action='store_true',
-                dest='debug_build',
-                default=False,
-                help="enable debug mode build" )
+    p.add_option( '-d', '--debug',
+                                action='store_true',
+                                dest='debug_build',
+                                default=False,
+                                help="enable debug mode build" )
 
-  p.add_option( '-c', '--checkcom',
-                action='store_true',
-                dest='check_command',
-                default=False,
-                help="check command line and exit without building" )
+    p.add_option( '-c', '--checkcom',
+                                action='store_true',
+                                dest='check_command',
+                                default=False,
+                                help="check command line and exit without building" )
 
-  p.add_option( '-y', '--deploy',
-                action='store_true',
-                dest='deploy_full',
-                default=False,
-                help="fully deploy built binaries" )
+    p.add_option( '-y', '--deploy',
+                                action='store_true',
+                                dest='deploy_full',
+                                default=False,
+                                help="fully deploy built binaries" )
 
-  p.add_option( '-Y', '--DEPLOY',
-                action='store_true',
-                dest='deploy_partial',
-                default=False,
-                help="deploy built binaries when non-OS-standard script language is chosen" )
+    p.add_option( '-Y', '--DEPLOY',
+                                action='store_true',
+                                dest='deploy_partial',
+                                default=False,
+                                help="deploy built binaries when non-OS-standard script language is chosen" )
 
-  p.add_option( '-v', '--verbose',
-                dest='deploy_verbose',
-                help="verbose level of `macdeployqt` tool" )
+    p.add_option( '-v', '--verbose',
+                                dest='deploy_verbose',
+                                help="verbose level of `macdeployqt` tool" )
 
-  p.add_option( '-?', '--??',
-                action='store_true',
-                dest='checkusage',
-                default=False,
-                help='check usage' )
+    p.add_option( '-?', '--??',
+                                action='store_true',
+                                dest='checkusage',
+                                default=False,
+                                help='check usage' )
 
-  p.set_defaults( type_qt        = "qt5macports",
-                  type_ruby      = "sys",
-                  type_python    = "sys",
-                  no_qt_binding  = False,
-                  make_option    = "-j4",
-                  debug_build    = False,
-                  check_command  = False,
-                  deploy_full    = False,
-                  deploy_partial = False,
-                  deploy_verbose = "1",
-                  checkusage     = False )
+    p.set_defaults( type_qt        = "qt5macports",
+                                    type_ruby      = "sys",
+                                    type_python    = "sys",
+                                    no_qt_binding  = False,
+                                    make_option    = "-j4",
+                                    debug_build    = False,
+                                    check_command  = False,
+                                    deploy_full    = False,
+                                    deploy_partial = False,
+                                    deploy_verbose = "1",
+                                    checkusage     = False )
 
-  opt, args = p.parse_args()
-  if (opt.checkusage):
-    print(Usage)
-    sys.exit(0)
+    opt, args = p.parse_args()
+    if (opt.checkusage):
+        print(Usage)
+        sys.exit(0)
 
-  # Determine the Qt type
-  candidates                = dict()
-  candidates['QT5MACPORTS'] = 'Qt5MacPorts'
-  candidates['QT5BREW']     = 'Qt5Brew'
-  candidates['QT5ANA3']     = 'Qt5Ana3'
-  try:
-    ModuleQt = candidates[ opt.type_qt.upper() ]
-  except KeyError:
-    ModuleQt = ''
-    pass
-  if ModuleQt == '':
-    print("")
-    print( "!!! Unknown Qt type <%s>. Case-insensitive candidates: %s" % \
-            (opt.type_qt, list(candidates.keys())), file=sys.stderr )
-    print(Usage)
-    sys.exit(1)
-  elif ModuleQt == "Qt5MacPorts":
-    choiceQt5 = 'qt5MP'
-  elif ModuleQt == "Qt5Brew":
-    choiceQt5 = 'qt5Brew'
-  elif ModuleQt == "Qt5Ana3":
-    choiceQt5 = 'qt5Ana3'
+    # Determine the Qt type
+    candidates                = dict()
+    candidates['QT5MACPORTS'] = 'Qt5MacPorts'
+    candidates['QT5BREW']     = 'Qt5Brew'
+    candidates['QT5ANA3']     = 'Qt5Ana3'
+    try:
+        ModuleQt = candidates[ opt.type_qt.upper() ]
+    except KeyError:
+        ModuleQt = ''
+        pass
+    if ModuleQt == '':
+        print("")
+        print( "!!! Unknown Qt type <%s>. Case-insensitive candidates: %s" % \
+                        (opt.type_qt, list(candidates.keys())), file=sys.stderr )
+        print(Usage)
+        sys.exit(1)
+    elif ModuleQt == "Qt5MacPorts":
+        choiceQt5 = 'qt5MP'
+    elif ModuleQt == "Qt5Brew":
+        choiceQt5 = 'qt5Brew'
+    elif ModuleQt == "Qt5Ana3":
+        choiceQt5 = 'qt5Ana3'
 
-  # By default, OS-standard (-bundled) script languages (Ruby and Python) are used
-  NonOSStdLang = False
+    # By default, OS-standard (-bundled) script languages (Ruby and Python) are used
+    NonOSStdLang = False
 
-  # Determine the Ruby type
-  candidates         = dict()
-  candidates['NIL']  = 'nil'
-  candidates['SYS']  = 'Sys'
-  candidates['MP26'] = 'MP26'
-  candidates['HB27'] = 'HB27'
-  candidates['ANA3'] = 'Ana3'
-  try:
-    choiceRuby = candidates[ opt.type_ruby.upper() ]
-  except KeyError:
-    ModuleRuby = ''
-    pass
-  else:
-    ModuleRuby = ''
-    if choiceRuby == "nil":
-      ModuleRuby = 'nil'
-    elif choiceRuby == "Sys":
-      choiceRuby = "Sys"
-      if Platform == "Catalina":
-        ModuleRuby = 'RubyCatalina'
-      elif Platform == "Mojave":
-        ModuleRuby = 'RubyMojave'
-      elif Platform == "HighSierra":
-        ModuleRuby = 'RubyHighSierra'
-      elif Platform == "Sierra":
-        ModuleRuby = 'RubySierra'
-      elif Platform == "ElCapitan":
-        ModuleRuby = 'RubyElCapitan'
-    elif choiceRuby == "MP26":
-      ModuleRuby   = 'Ruby26MacPorts'
-      NonOSStdLang = True
-    elif choiceRuby == "HB27":
-      ModuleRuby   = 'Ruby27Brew'
-      NonOSStdLang = True
-    elif choiceRuby == "Ana3":
-      ModuleRuby   = 'RubyAnaconda3'
-      NonOSStdLang = True
-  if ModuleRuby == '':
-    print("")
-    print( "!!! Unknown Ruby type <%s>. Case-insensitive candidates: %s" % \
-            (opt.type_ruby, list(candidates.keys())), file=sys.stderr )
-    print(Usage)
-    sys.exit(1)
+    # Determine the Ruby type
+    candidates         = dict()
+    candidates['NIL']  = 'nil'
+    candidates['SYS']  = 'Sys'
+    candidates['MP26'] = 'MP26'
+    candidates['HB27'] = 'HB27'
+    candidates['ANA3'] = 'Ana3'
+    try:
+        choiceRuby = candidates[ opt.type_ruby.upper() ]
+    except KeyError:
+        ModuleRuby = ''
+        pass
+    else:
+        ModuleRuby = ''
+        if choiceRuby == "nil":
+            ModuleRuby = 'nil'
+        elif choiceRuby == "Sys":
+            choiceRuby = "Sys"
+            if Platform == "Catalina":
+                ModuleRuby = 'RubyCatalina'
+            elif Platform == "Mojave":
+                ModuleRuby = 'RubyMojave'
+            elif Platform == "HighSierra":
+                ModuleRuby = 'RubyHighSierra'
+            elif Platform == "Sierra":
+                ModuleRuby = 'RubySierra'
+            elif Platform == "ElCapitan":
+                ModuleRuby = 'RubyElCapitan'
+        elif choiceRuby == "MP26":
+            ModuleRuby   = 'Ruby26MacPorts'
+            NonOSStdLang = True
+        elif choiceRuby == "HB27":
+            ModuleRuby   = 'Ruby27Brew'
+            NonOSStdLang = True
+        elif choiceRuby == "Ana3":
+            ModuleRuby   = 'RubyAnaconda3'
+            NonOSStdLang = True
+    if ModuleRuby == '':
+        print("")
+        print( "!!! Unknown Ruby type <%s>. Case-insensitive candidates: %s" % \
+                        (opt.type_ruby, list(candidates.keys())), file=sys.stderr )
+        print(Usage)
+        sys.exit(1)
 
-  # Determine the Python type
-  candidates         = dict()
-  candidates['NIL']  = 'nil'
-  candidates['SYS']  = 'Sys'
-  candidates['MP37'] = 'MP37'
-  candidates['HB37'] = 'HB37'
-  candidates['ANA3'] = 'Ana3'
-  try:
-    choicePython = candidates[ opt.type_python.upper() ]
-  except KeyError:
-    ModulePython = ''
-    pass
-  else:
-    ModulePython = ''
-    if choicePython ==  "nil":
-      ModulePython = 'nil'
-    elif choicePython == "Sys":
-      if Platform == "Catalina":
-        ModulePython = 'PythonCatalina'
-      elif Platform == "Mojave":
-        ModulePython = 'PythonMojave'
-      elif Platform == "HighSierra":
-        ModulePython = 'PythonHighSierra'
-      elif Platform == "Sierra":
-        ModulePython = 'PythonSierra'
-      elif Platform == "ElCapitan":
-        ModulePython = 'PythonElCapitan'
-    elif choicePython == "MP37":
-      ModulePython = 'Python37MacPorts'
-      NonOSStdLang = True
-    elif choicePython == "HB37":
-      ModulePython = 'Python37Brew'
-      NonOSStdLang = True
-    elif choicePython == "Ana3":
-      ModulePython = 'PythonAnaconda3'
-      NonOSStdLang = True
-  if ModulePython == '':
-    print("")
-    print( "!!! Unknown Python type <%s>. Case-insensitive candidates: %s" % \
-            (opt.type_python, list(candidates.keys())), file=sys.stderr )
-    print(Usage)
-    sys.exit(1)
+    # Determine the Python type
+    candidates         = dict()
+    candidates['NIL']  = 'nil'
+    candidates['SYS']  = 'Sys'
+    candidates['MP38'] = 'MP38'
+    candidates['HB38'] = 'HB38'
+    candidates['ANA3'] = 'Ana3'
+    try:
+        choicePython = candidates[ opt.type_python.upper() ]
+    except KeyError:
+        ModulePython = ''
+        pass
+    else:
+        ModulePython = ''
+        if choicePython ==  "nil":
+            ModulePython = 'nil'
+        elif choicePython == "Sys":
+            if Platform == "Catalina":
+                ModulePython = 'PythonCatalina'
+            elif Platform == "Mojave":
+                ModulePython = 'PythonMojave'
+            elif Platform == "HighSierra":
+                ModulePython = 'PythonHighSierra'
+            elif Platform == "Sierra":
+                ModulePython = 'PythonSierra'
+            elif Platform == "ElCapitan":
+                ModulePython = 'PythonElCapitan'
+        elif choicePython == "MP38":
+            ModulePython = 'Python38MacPorts'
+            NonOSStdLang = True
+        elif choicePython == "HB38":
+            ModulePython = 'Python38Brew'
+            NonOSStdLang = True
+        elif choicePython == "Ana3":
+            ModulePython = 'PythonAnaconda3'
+            NonOSStdLang = True
+    if ModulePython == '':
+        print("")
+        print( "!!! Unknown Python type <%s>. Case-insensitive candidates: %s" % \
+                        (opt.type_python, list(candidates.keys())), file=sys.stderr )
+        print(Usage)
+        sys.exit(1)
 
-  # Set of modules chosen
-  ModuleSet = ( choiceQt5, choiceRuby, choicePython )
+    # Set of modules chosen
+    ModuleSet = ( choiceQt5, choiceRuby, choicePython )
 
-  NoQtBindings  = opt.no_qt_binding
-  MakeOptions   = opt.make_option
-  DebugMode     = opt.debug_build
-  CheckComOnly  = opt.check_command
-  DeploymentF   = opt.deploy_full
-  DeploymentP   = opt.deploy_partial
+    NoQtBindings = opt.no_qt_binding
+    MakeOptions  = opt.make_option
+    DebugMode    = opt.debug_build
+    CheckComOnly = opt.check_command
+    DeploymentF  = opt.deploy_full
+    DeploymentP  = opt.deploy_partial
 
-  if DeploymentF and DeploymentP:
-    print("")
-    print( "!!! Choose either [-y|--deploy] or [-Y|--DEPLOY]", file=sys.stderr )
-    print(Usage)
-    sys.exit(1)
+    if DeploymentF and DeploymentP:
+        print("")
+        print( "!!! Choose either [-y|--deploy] or [-Y|--DEPLOY]", file=sys.stderr )
+        print(Usage)
+        sys.exit(1)
 
-  DeployVerbose = int(opt.deploy_verbose)
-  if not DeployVerbose in [0, 1, 2, 3]:
-    print("")
-    print( "!!! Unsupported verbose level passed to `macdeployqt` tool", file=sys.stderr )
-    print(Usage)
-    sys.exit(1)
+    DeployVerbose = int(opt.deploy_verbose)
+    if not DeployVerbose in [0, 1, 2, 3]:
+        print("")
+        print( "!!! Unsupported verbose level passed to `macdeployqt` tool", file=sys.stderr )
+        print(Usage)
+        sys.exit(1)
 
-  if not DeploymentF and not DeploymentP:
-    target  = "%s %s %s" % (Platform, Release, Machine)
-    modules = "Qt=%s, Ruby=%s, Python=%s" % (ModuleQt, ModuleRuby, ModulePython)
-    message = "### You are going to build KLayout\n    for  <%s>\n    with <%s>...\n"
-    print("")
-    print( message % (target, modules) )
-  else:
-    message = "### You are going to make "
-    if DeploymentP:
-      PackagePrefix = "LW-"
-      message      += "a llightweight (LW-) package excluding Qt5, Ruby, and Python..."
-    elif DeploymentF:
-      if (ModuleRuby in RubySys) and (ModulePython in PythonSys):
-        PackagePrefix = "ST-"
-        message      += "a standard (ST-) package including Qt5 and using OS-bundled Ruby and Python..."
-      elif ModulePython == 'Python37Brew':
-        PackagePrefix = "HW-"
-        message      += "a heavyweight (HW-) package including Qt5 and Python3.7 from Homebrew..."
-      else:
-        PackagePrefix = "EX-"
-        message      += "a package with exceptional (EX-) combinations of different modules..."
-    print( "" )
-    print( message )
-    print( "" )
-    if CheckComOnly:
-      sys.exit(0)
+    if not DeploymentF and not DeploymentP:
+        target  = "%s %s %s" % (Platform, Release, Machine)
+        modules = "Qt=%s, Ruby=%s, Python=%s" % (ModuleQt, ModuleRuby, ModulePython)
+        message = "### You are going to build KLayout\n    for  <%s>\n    with <%s>...\n"
+        print("")
+        print( message % (target, modules) )
+    else:
+        message = "### You are going to make "
+        if DeploymentP:
+            PackagePrefix = "LW-"
+            message      += "a lightweight (LW-) package excluding Qt5, Ruby, and Python..."
+        elif DeploymentF:
+            if (ModuleRuby in RubySys) and (ModulePython in PythonSys):
+                PackagePrefix = "ST-"
+                message      += "a standard (ST-) package including Qt5 and using OS-bundled Ruby and Python..."
+            elif ModulePython == 'Python38Brew':
+                PackagePrefix = "HW-"
+                message      += "a heavyweight (HW-) package including Qt5 and Python3.8 from Homebrew..."
+            else:
+                PackagePrefix = "EX-"
+                message      += "a package with exceptional (EX-) combinations of different modules..."
+        print( "" )
+        print( message )
+        print( "" )
+        if CheckComOnly:
+            sys.exit(0)
+
+    config['Usage']         = Usage         #
+    config['Platform']      = Platform      #
+    config['ModuleQt']      = ModuleQt      #
+    config['ModuleRuby']    = ModuleRuby    #
+    config['ModulePython']  = ModulePython  #
+    config['NonOSStdLang']  = NonOSStdLang  #
+    config['NoQtBindings']  = NoQtBindings  #
+    config['MakeOptions']   = MakeOptions   #
+    config['DebugMode']     = DebugMode     #
+    config['CheckComOnly']  = CheckComOnly  #
+    config['DeploymentF']   = DeploymentF   #
+    config['DeploymentP']   = DeploymentP   #
+    config['PackagePrefix'] = PackagePrefix #
+    config['DeployVerbose'] = DeployVerbose #
+    config['ModuleSet']     = ModuleSet     #
+
+    return config
 
 #------------------------------------------------------------------------------
 ## To run the main Bash script "build.sh" with appropriate options
 #
 # @return 0 on success; non-zero on failure
 #------------------------------------------------------------------------------
-def RunMainBuildBash():
-  global ProjectDir
-  global Platform
-  global BuildBash
-  global ModuleQt
-  global ModuleRuby
-  global ModulePython
-  global ModuleSet
-  global NoQtBindings
-  global MakeOptions
-  global DebugMode
-  global CheckComOnly
-  global DeploymentF
-  global DeploymentP
-  global PackagePrefix
-  global MacPkgDir          # relative path to package directory
-  global MacBinDir          # relative path to binary directory
-  global MacBuildDir        # relative path to build directory
-  global MacBuildDirQAT     # relative path to build directory for QATest
-  global MacBuildLog        # relative path to build log file
-  global AbsMacPkgDir       # absolute path to package directory
-  global AbsMacBinDir       # absolute path to binary directory
-  global AbsMacBuildDir     # absolute path to build directory
-  global AbsMacBuildDirQAT  # absolute path to build directory for QATest
-  global AbsMacBuildLog     # absolute path to build log file
+def get_build_parameters(config):
+    ProjectDir    = config['ProjectDir']     #
+    Platform      = config['Platform']       #
+    BuildBash     = config['BuildBash']      #
+    ModuleQt      = config['ModuleQt']       #
+    ModuleRuby    = config['ModuleRuby']     #
+    ModulePython  = config['ModulePython']   #
+    ModuleSet     = config['ModuleSet']      #
+    NoQtBindings  = config['NoQtBindings']   #
+    MakeOptions   = config['MakeOptions']    #
+    DebugMode     = config['DebugMode']      #
+    CheckComOnly  = config['CheckComOnly']   #
+    DeploymentF   = config['DeploymentF']    #
+    DeploymentP   = config['DeploymentP']    #
+    PackagePrefix = config['PackagePrefix']  #
 
-  #-----------------------------------------------------
-  # [1] Set parameters passed to the main Bash script
-  #-----------------------------------------------------
-  parameters = ""
+    #-----------------------------------------------------
+    # [1] Set parameters passed to the main Bash script
+    #-----------------------------------------------------
+    parameters = dict()
 
-  # (A) debug or release
-  if DebugMode:
-    mode        = "debug"
-    parameters += "  -debug"
-  else:
-    mode        = "release"
-    parameters += "  -release"
+    parameters['build_cmd'] = BuildBash
+    parameters['check_cmd_only'] = CheckComOnly
 
-  # (B) Modules
-  (qt, ruby, python) = ModuleSet  # ( 'qt5MP', 'Sys', 'Sys' )
-  ruby_python = "R%sP%s" % ( ruby.lower(), python.lower() )
-
-  # (C) Target directories and files
-  MacPkgDir         = "./%s%s.pkg.macos-%s-%s-%s"      % (PackagePrefix, qt, Platform, mode, ruby_python)
-  MacBinDir         = "./%s.bin.macos-%s-%s-%s"        % (               qt, Platform, mode, ruby_python)
-  MacBuildDir       = "./%s.build.macos-%s-%s-%s"      % (               qt, Platform, mode, ruby_python)
-  MacBuildLog       = "./%s.build.macos-%s-%s-%s.log"  % (               qt, Platform, mode, ruby_python)
-  AbsMacPkgDir      = "%s/%s%s.pkg.macos-%s-%s-%s"     % (ProjectDir, PackagePrefix, qt, Platform, mode, ruby_python)
-  AbsMacBinDir      = "%s/%s.bin.macos-%s-%s-%s"       % (ProjectDir,                qt, Platform, mode, ruby_python)
-  AbsMacBuildDir    = "%s/%s.build.macos-%s-%s-%s"     % (ProjectDir,                qt, Platform, mode, ruby_python)
-  AbsMacBuildLog    = "%s/%s.build.macos-%s-%s-%s.log" % (ProjectDir,                qt, Platform, mode, ruby_python)
-  MacBuildDirQAT    = MacBuildDir    + ".macQAT"
-  AbsMacBuildDirQAT = AbsMacBuildDir + ".macQAT"
-
-  # (D) Qt5
-  if ModuleQt == 'Qt5MacPorts':
-    parameters    += " \\\n  -qt5"
-    parameters    += " \\\n  -qmake  %s" % Qt5MacPorts['qmake']
-    parameters    += " \\\n  -bin    %s" % MacBinDir
-    parameters    += " \\\n  -build  %s" % MacBuildDir
-  elif ModuleQt == 'Qt5Brew':
-    parameters    += " \\\n  -qt5"
-    parameters    += " \\\n  -qmake  %s" % Qt5Brew['qmake']
-    parameters    += " \\\n  -bin    %s" % MacBinDir
-    parameters    += " \\\n  -build  %s" % MacBuildDir
-  elif ModuleQt == 'Qt5Ana3':
-    parameters    += " \\\n  -qt5"
-    parameters    += " \\\n  -qmake  %s" % Qt5Ana3['qmake']
-    parameters    += " \\\n  -bin    %s" % MacBinDir
-    parameters    += " \\\n  -build  %s" % MacBuildDir
-  parameters += " \\\n  -rpath    %s" % "@executable_path/../Frameworks"
-
-  # (E) want Qt bindings with Ruby scripts?
-  if NoQtBindings:
-    parameters += " \\\n  -without-qtbinding"
-  else:
-    parameters += " \\\n  -with-qtbinding"
-
-  # (F) options to `make` tool
-  if not MakeOptions == "":
-    parameters += " \\\n  -option %s" % MakeOptions
-
-  # (G) about Ruby
-  if ModuleRuby == "nil":
-    parameters += " \\\n  -noruby"
-  else:
-    parameters += " \\\n  -ruby   %s" % RubyDictionary[ModuleRuby]['exe']
-    parameters += " \\\n  -rbinc  %s" % RubyDictionary[ModuleRuby]['inc']
-    parameters += " \\\n  -rblib  %s" % RubyDictionary[ModuleRuby]['lib']
-
-  # (H) about Python
-  if ModulePython == "nil":
-    parameters += " \\\n  -nopython"
-  else:
-    parameters += " \\\n  -python %s" % PythonDictionary[ModulePython]['exe']
-    parameters += " \\\n  -pyinc  %s" % PythonDictionary[ModulePython]['inc']
-    parameters += " \\\n  -pylib  %s" % PythonDictionary[ModulePython]['lib']
-
-  #-----------------------------------------------------
-  # [2] Make the consolidated command line
-  #-----------------------------------------------------
-  command  = "time"
-  command += " \\\n  %s" % BuildBash
-  command += parameters
-  command += "  2>&1 | tee %s" % MacBuildLog
-  if CheckComOnly:
-    print(command)
-    sys.exit(0)
-
-  #-----------------------------------------------------
-  # [3] Invoke the main Bash script; takes time:-)
-  #-----------------------------------------------------
-  if DeploymentF:
-    return 0
-  elif DeploymentP:
-    return 0
-  else:
-    myscript = "build4mac.py"
-    if subprocess.call( command, shell=True ) != 0:
-      print( "", file=sys.stderr )
-      print( "-------------------------------------------------------------", file=sys.stderr )
-      print( "!!! <%s>: failed to build KLayout" % myscript, file=sys.stderr )
-      print( "-------------------------------------------------------------", file=sys.stderr )
-      print( "", file=sys.stderr )
-      return 1
+    # (A) debug or release
+    parameters['debug_mode'] = DebugMode  # True if debug, False if release
+    if parameters["debug_mode"]:
+        mode        = "debug"
     else:
-      print( "", file=sys.stderr )
-      print( "+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++", file=sys.stderr )
-      print( "### <%s>: successfully built KLayout" % myscript, file=sys.stderr )
-      print( "+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++", file=sys.stderr )
-      print( "", file=sys.stderr )
+        mode        = "release"
 
-      #------------------------------------------------------------------------
-      # [4] Prepare "*.macQAT/" directory for the QATest.
-      #     Binaries under "*.macQAT/" such as *.dylib will be touched later.
-      #------------------------------------------------------------------------
-      print( "### Preparing <%s>" % MacBuildDirQAT )
-      if os.path.isdir( MacBuildDirQAT ):
+    # (B) Modules
+    (qt, ruby, python) = ModuleSet  # ( 'qt5MP', 'Sys', 'Sys' )
+    ruby_python = "R%sP%s" % ( ruby.lower(), python.lower() )
+
+    # (C) Target directories and files
+    MacPkgDir         = "%s%s.pkg.macos-%s-%s-%s"        % (PackagePrefix, qt, Platform, mode, ruby_python)
+    MacBinDir         = "%s.bin.macos-%s-%s-%s"          % (               qt, Platform, mode, ruby_python)
+    MacBuildDir       = "%s.build.macos-%s-%s-%s"        % (               qt, Platform, mode, ruby_python)
+    MacBuildLog       = "%s.build.macos-%s-%s-%s.log"    % (               qt, Platform, mode, ruby_python)
+    # AbsMacPkgDir      = "%s/%s%s.pkg.macos-%s-%s-%s"     % (ProjectDir, PackagePrefix, qt, Platform, mode, ruby_python)
+    # AbsMacBinDir      = "%s/%s.bin.macos-%s-%s-%s"       % (ProjectDir,                qt, Platform, mode, ruby_python)
+    # AbsMacBuildDir    = "%s/%s.build.macos-%s-%s-%s"     % (ProjectDir,                qt, Platform, mode, ruby_python)
+    # AbsMacBuildLog    = "%s/%s.build.macos-%s-%s-%s.log" % (ProjectDir,                qt, Platform, mode, ruby_python)
+    # AbsMacPkgDir      = "%s/%s"                          % (ProjectDir, MacPkgDir)
+    # AbsMacBinDir      = "%s/%s"                          % (ProjectDir, MacBinDir)
+    # AbsMacBuildDir    = "%s/%s"                          % (ProjectDir, MacBuildDir)
+    # AbsMacBuildLog    = "%s/%s"                          % (ProjectDir, MacBuildLog)
+
+    MacBuildDirQAT    = MacBuildDir    + ".macQAT"
+    parameters['logfile'] = MacBuildLog
+
+    # (D) Qt5
+    if ModuleQt == 'Qt5MacPorts':
+        parameters['qmake'] = Qt5MacPorts['qmake']
+        parameters['deploy_tool'] = Qt5MacPorts['deploy']
+    elif ModuleQt == 'Qt5Brew':
+        parameters['qmake'] = Qt5Brew['qmake']
+        parameters['deploy_tool'] = Qt5Brew['deploy']
+    elif ModuleQt == 'Qt5Ana3':
+        parameters['qmake'] = Qt5Ana3['qmake']
+        parameters['deploy_tool'] = Qt5Ana3['deploy']
+
+    parameters['bin'] = MacBinDir
+    parameters['build'] = MacBuildDir
+    parameters['rpath'] = "@executable_path/../Frameworks"
+
+    # (E) want Qt bindings with Ruby scripts?
+    parameters['no_qt_bindings'] = NoQtBindings
+
+    # (F) options to `make` tool
+    if not MakeOptions == "":
+        parameters['make_options'] = MakeOptions
+
+    # (G) about Ruby
+    if ModuleRuby != "nil":
+        parameters['ruby'] = RubyDictionary[ModuleRuby]['exe']
+        parameters['rbinc'] = RubyDictionary[ModuleRuby]['inc']
+        parameters['rblib'] = RubyDictionary[ModuleRuby]['lib']
+        if 'inc2' in RubyDictionary[ModuleRuby]:
+            parameters['rbinc2'] = RubyDictionary[ModuleRuby]['inc2']
+
+    # (H) about Python
+    if ModulePython != "nil":
+        parameters['python'] = PythonDictionary[ModulePython]['exe']
+        parameters['pyinc'] = PythonDictionary[ModulePython]['inc']
+        parameters['pylib'] = PythonDictionary[ModulePython]['lib']
+
+    config['MacPkgDir']         = MacPkgDir          # relative path to package directory
+    config['MacBinDir']         = MacBinDir          # relative path to binary directory
+    config['MacBuildDir']       = MacBuildDir        # relative path to build directory
+    config['MacBuildDirQAT']    = MacBuildDirQAT     # relative path to build directory for QATest
+    config['MacBuildLog']       = MacBuildLog        # relative path to build log file
+    # config['AbsMacPkgDir']      = AbsMacPkgDir       # absolute path to package directory
+    # config['AbsMacBinDir']      = AbsMacBinDir       # absolute path to binary directory
+    # config['AbsMacBuildDir']    = AbsMacBuildDir     # absolute path to build directory
+    # config['AbsMacBuildDirQAT'] = AbsMacBuildDirQAT  # absolute path to build directory for QATest
+    # config['AbsMacBuildLog']    = AbsMacBuildLog     # absolute path to build log file
+
+    # Extra parameteres needed for deployment
+    parameters['project_dir'] = ProjectDir
+
+    return parameters
+
+def run_build_command(parameters):
+
+    #-----------------------------------------------------
+    # [1] Set parameters passed to the main Bash script
+    #-----------------------------------------------------
+
+    cmd_args = ""
+
+    # (A) debug or release
+    if parameters["debug_mode"]:
+        mode        = "debug"
+        cmd_args += "  -debug"
+    else:
+        mode        = "release"
+        cmd_args += "  -release"
+
+    # (C) Target directories and files
+    MacBuildDirQAT    = parameters['build']    + ".macQAT"
+
+    # (D) Qt5
+    cmd_args    += " \\\n  -qt5"
+    cmd_args    += " \\\n  -qmake  %s" % parameters['qmake']
+    cmd_args    += " \\\n  -bin    %s" % parameters['bin']
+    cmd_args    += " \\\n  -build  %s" % parameters['build']
+    cmd_args += " \\\n  -rpath    %s" % parameters['rpath']
+
+    # (E) want Qt bindings with Ruby scripts?
+    if parameters['no_qt_bindings']:
+        cmd_args += " \\\n  -without-qtbinding"
+    else:
+        cmd_args += " \\\n  -with-qtbinding"
+
+    # (F) options to `make` tool
+    if 'make_options' in parameters:
+        cmd_args += " \\\n  -option %s" % parameters['make_options']
+
+    # (G) about Ruby
+    if 'ruby' in parameters:
+        cmd_args += " \\\n  -ruby   %s" % parameters['ruby']
+        cmd_args += " \\\n  -rbinc  %s" % parameters['rbinc']
+        cmd_args += " \\\n  -rblib  %s" % parameters['rblib']
+        if 'rbinc2' in parameters:
+            cmd_args += " \\\n  -rbinc2  %s" % parameters['rbinc2']
+    else:
+        cmd_args += " \\\n  -noruby"
+
+    # (H) about Python
+    if 'python' in parameters:
+        cmd_args += " \\\n  -python %s" % parameters['python']
+        cmd_args += " \\\n  -pyinc  %s" % parameters['pyinc']
+        cmd_args += " \\\n  -pylib  %s" % parameters['pylib']
+    else:
+        cmd_args += " \\\n  -nopython"
+
+    #-----------------------------------------------------
+    # [2] Make the consolidated command line
+    #-----------------------------------------------------
+    command  = "time"
+    command += " \\\n  %s" % parameters['build_cmd']
+    command += cmd_args
+    command += "  2>&1 | tee %s; \\\n" % parameters['logfile']
+    command += "test ${PIPESTATUS[0]} -eq 0"  # tee always exits with 0
+
+    if parameters['check_cmd_only']:
+        print(command)
+        sys.exit(0)
+
+    #-----------------------------------------------------
+    # [3] Invoke the main Bash script; takes time:-)
+    #-----------------------------------------------------
+
+    myscript = os.path.basename(__file__)
+    ret = subprocess.call( command, shell=True )
+    if ret != 0:
+        print( "", file=sys.stderr )
+        print( "-------------------------------------------------------------", file=sys.stderr )
+        print( "!!! <%s>: failed to build KLayout" % myscript, file=sys.stderr )
+        print( "-------------------------------------------------------------", file=sys.stderr )
+        print( "", file=sys.stderr )
+        return 1
+
+    print( "", file=sys.stderr )
+    print( "+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++", file=sys.stderr )
+    print( "### <%s>: successfully built KLayout" % myscript, file=sys.stderr )
+    print( "+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++", file=sys.stderr )
+    print( "", file=sys.stderr )
+
+    #------------------------------------------------------------------------
+    # [4] Prepare "*.macQAT/" directory for the QATest.
+    #     Binaries under "*.macQAT/" such as *.dylib will be touched later.
+    #------------------------------------------------------------------------
+    print( "### Preparing <%s>" % MacBuildDirQAT )
+    if os.path.isdir( MacBuildDirQAT ):
         shutil.rmtree( MacBuildDirQAT )
 
-      os.chdir( MacBuildDir )
-      tarFile = "../macQATest.tar"
-      tarCmdC = "tar cf %s ." % tarFile
-      if subprocess.call( tarCmdC, shell=True ) != 0:
+    os.chdir( parameters['build'] )
+    tarFile = "../macQATest.tar"
+    tarCmdC = "tar cf %s ." % tarFile
+    if subprocess.call( tarCmdC, shell=True ) != 0:
         print( "", file=sys.stderr )
         print( "-------------------------------------------------------------", file=sys.stderr )
         print( "!!! <%s>: failed to create <%s>" % (myscript, tarFile), file=sys.stderr )
@@ -578,11 +689,11 @@ def RunMainBuildBash():
         print( "", file=sys.stderr )
         return 1
 
-      os.chdir( "../" )
-      os.mkdir( MacBuildDirQAT )
-      os.chdir( MacBuildDirQAT )
-      tarCmdX = "tar xf %s" % tarFile
-      if subprocess.call( tarCmdX, shell=True ) != 0:
+    os.chdir( "../" )
+    os.mkdir( MacBuildDirQAT )
+    os.chdir( MacBuildDirQAT )
+    tarCmdX = "tar xf %s" % tarFile
+    if subprocess.call( tarCmdX, shell=True ) != 0:
         print( "", file=sys.stderr )
         print( "-------------------------------------------------------------", file=sys.stderr )
         print( "!!! <%s>: failed to unpack <%s>" % (myscript, tarFile), file=sys.stderr )
@@ -590,14 +701,15 @@ def RunMainBuildBash():
         print( "", file=sys.stderr )
         return 1
 
-      os.remove( tarFile )
-      os.chdir( "../" )
-      shutil.copy2( "macbuild/macQAT.sh", MacBuildDirQAT )
-      print( "+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++", file=sys.stderr )
-      print( "### <%s>: prepared the initial *.macQAT/" % myscript, file=sys.stderr )
-      print( "+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++", file=sys.stderr )
-      print( "", file=sys.stderr )
-      return 0
+    os.remove( tarFile )
+    os.chdir( "../" )
+    shutil.copy2( "macbuild/macQAT.sh", MacBuildDirQAT )
+    shutil.copy2( "macbuild/macQAT.py", MacBuildDirQAT )
+    print( "+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++", file=sys.stderr )
+    print( "### <%s>: prepared the initial *.macQAT/" % myscript, file=sys.stderr )
+    print( "+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++", file=sys.stderr )
+    print( "", file=sys.stderr )
+    return 0
 
 #------------------------------------------------------------------------------
 ## For making a bundle (klayout.app), deploy built binaries and libraries
@@ -607,501 +719,525 @@ def RunMainBuildBash():
 #
 # @return 0 on success; non-zero on failure
 #------------------------------------------------------------------------------
-def DeployBinariesForBundle():
-  global ProjectDir
-  global ModuleQt
-  global NonOSStdLang
-  global DeploymentF
-  global DeploymentP
-  global MacPkgDir
-  global MacBinDir
-  global MacBuildDir
-  global MacBuildDirQAT
-  global MacBuildLog
-  global AbsMacPkgDir
-  global AbsMacBinDir
-  global AbsMacBuildDir
-  global AbsMacBuildDirQAT
-  global AbsMacBuildLog
-  global Version
-  global DeployVerbose
+def DeployBinariesForBundle(config, parameters):
+    NonOSStdLang   = config['NonOSStdLang']
+    DeploymentF    = config['DeploymentF']
+    DeploymentP    = config['DeploymentP']
+    MacPkgDir      = config['MacPkgDir']
+    Version        = config['Version']
+    DeployVerbose  = config['DeployVerbose']
+    ModuleRuby     = config['ModuleRuby']
+    ModulePython   = config['ModulePython']
 
-  print("")
-  print( "##### Started deploying libraries and executables for <klayout.app> #####" )
-  print( " [1] Checking the status of working directory ..." )
-  #-------------------------------------------------------------
-  # [1] Check the status of working directory
-  #-------------------------------------------------------------
-  os.chdir(ProjectDir)
-  if not DeploymentF and not DeploymentP:
-    return 1
-  if DeploymentF and NonOSStdLang:
-    print( "     WARNING!!! You chose <-y|--deploy> while using non-OS-standard script language.", file=sys.stderr )
-    print( "         Consider using <-Y|--DEPLOY> instead", file=sys.stderr )
-    #return 1
-  if not os.path.isfile(MacBuildLog):
-    print( "!!! Build log file <%s> does not present !!!" % MacBuildLog, file=sys.stderr )
-    return 1
-  if not os.path.isdir(MacBuildDir):
-    print( "!!! Build directory <%s> does not present !!!" % MacBuildDir, file=sys.stderr )
-    return 1
-  if not os.path.isdir(MacBinDir):
-    print( "!!! Binary directory <%s> does not present !!!" % MacBinDir, file=sys.stderr )
-    return 1
+    ProjectDir  = parameters['project_dir']
+    MacBinDir   = parameters['bin']
+    MacBuildDir = parameters['build']
+    MacBuildLog = parameters['logfile']
 
+    AbsMacPkgDir     = "%s/%s" % (ProjectDir, MacPkgDir)
+    AbsMacBinDir     = "%s/%s" % (ProjectDir, MacBinDir)
+    AbsMacBuildDir   = "%s/%s" % (ProjectDir, MacBuildDir)
+    AbsMacBuildLog   = "%s/%s" % (ProjectDir, MacBuildLog)
 
-  print( " [2] Creating a new empty directory <%s> for deployment ..." % MacPkgDir )
-  #-------------------------------------------------------------
-  # [2] Create a new empty directory for deploying binaries
-  #-------------------------------------------------------------
-  os.chdir(ProjectDir)
-  if os.path.isfile(MacPkgDir):
-    os.remove(MacPkgDir)
-  if os.path.isdir(MacPkgDir):
-    shutil.rmtree(MacPkgDir)
-  os.mkdir(MacPkgDir)
-
-
-  print( " [3] Creating the standard directory structure for 'klayout.app' bundle ..." )
-  #-----------------------------------------------------------------
-  # [3] Create the directory skeleton for "klayout.app" bundle
-  #     and command line buddy tools such as "strm2cif".
-  #     They are stored in the directory structure below.
-  #
-  #    klayout.app/+
-  #                +-- Contents/+
-  #                             +-- Info.plist
-  #                             +-- PkgInfo
-  #                             +-- Resources/+
-  #                             |             +-- 'klayout.icns'
-  #                             +-- Frameworks/+
-  #                             |              +-- '*.framework'
-  #                             |              +-- '*.dylib'
-  #                             |              +-- 'db_plugins' --slink--> ../MacOS/db_plugins/
-  #                             +-- MacOS/+
-  #                             |         +-- 'klayout'
-  #                             |         +-- db_plugins/
-  #                             |         +-- lay_plugins/
-  #                             +-- Buddy/+
-  #                                       +-- 'strm2cif'
-  #                                       +-- 'strm2dxf'
-  #                                       :
-  #                                       +-- 'strmxor'
-  #-----------------------------------------------------------------
-  targetDir0 = "%s/klayout.app/Contents" % AbsMacPkgDir
-  targetDirR = targetDir0 + "/Resources"
-  targetDirF = targetDir0 + "/Frameworks"
-  targetDirM = targetDir0 + "/MacOS"
-  targetDirB = targetDir0 + "/Buddy"
-  os.makedirs(targetDirR)
-  os.makedirs(targetDirF)
-  os.makedirs(targetDirM)
-  os.makedirs(targetDirB)
-
-
-  print( " [4] Copying KLayout's dynamic link libraries to 'Frameworks' ..." )
-  #-------------------------------------------------------------------------------
-  # [4] Copy KLayout's dynamic link libraries to "Frameworks/" and create
-  #     the library dependency dictionary.
-  #     <<< Do this job in "Frameworks/" >>>
-  #
-  # Note:
-  #     KLayout's dynamic link library is built as below:
-  #       (1) libklayout_lay.0.26.1.dylib
-  #       (2) libklayout_lay.0.26.dylib -> libklayout_lay.0.26.1.dylib
-  #       (3) libklayout_lay.0.dylib -> libklayout_lay.0.26.1.dylib
-  #       (4) libklayout_lay.dylib -> libklayout_lay.0.26.1.dylib
-  #     where,
-  #       (1) is an ordinary file with full version number 'major.minor.teeny'
-  #           between "library_name."='libklayout_lay.' and '.dylib'
-  #       (2) is a symbolic link with 'major.minor' version number
-  #       (3) is a symbolic link with 'major' version number
-  #       (4) is a symbolic link without version number number
-  #
-  #     The dynamic linker tries to find a library name in style (3) as shown
-  #     in the example below.
-  #
-  # Example:
-  #   MacBookPro2(1)$ otool -L klayout
-  #   klayout:
-  #       :
-  #       :
-  #     libklayout_tl.0.dylib (compatibility version 0.26.0, current version 0.26.1)
-  #     libklayout_gsi.0.dylib (compatibility version 0.26.0, current version 0.26.1)
-  #     libklayout_db.0.dylib (compatibility version 0.26.0, current version 0.26.1)
-  #       :
-  #-------------------------------------------------------------------------------
-  os.chdir( targetDirF )
-  dynamicLinkLibs = glob.glob( os.path.join( AbsMacBinDir, "*.dylib" ) )
-  depDicOrdinary  = {} # inter-library dependency dictionary
-  pathDic = {} # paths to insert for each library
-  for item in dynamicLinkLibs:
-    if os.path.isfile(item) and not os.path.islink(item):
-      #-------------------------------------------------------------------
-      # (A) Copy an ordinary *.dylib file here by changing the name
-      #     to style (3) and set its mode to 0755 (sanity check).
-      #-------------------------------------------------------------------
-      fullName = os.path.basename(item).split('.')
-      # e.g. [ 'libklayout_lay', '0', '26', '1', 'dylib' ]
-      nameStyle3 = fullName[0] + "." + fullName[1] + ".dylib"
-      shutil.copy2( item, nameStyle3 )
-      os.chmod( nameStyle3, 0o0755 )
-      #-------------------------------------------------------------------
-      # (B) Then get inter-library dependencies
-      #     Note that will pull all dependencies and sort them out later
-      #     dropping those which don't have a path entry
-      #-------------------------------------------------------------------
-      otoolCm   = "otool -L %s | grep dylib" % nameStyle3
-      otoolOut  = os.popen( otoolCm ).read()
-      dependDic = DecomposeLibraryDependency(otoolOut)
-      depDicOrdinary.update(dependDic)
-      #-------------------------------------------------------------------
-      # (C) This library goes into Frameworks, hence record it's path there
-      #-------------------------------------------------------------------
-      pathDic[nameStyle3] = "@executable_path/../Frameworks/" + nameStyle3
-
-  os.chdir(ProjectDir)
-  #-------------------------------------------------------------------
-  # Copy the contents of the plugin directories to a place next to
-  # the application binary
-  #-------------------------------------------------------------------
-  for piDir in [ "db_plugins", "lay_plugins" ]:
-    os.makedirs( os.path.join( targetDirM, piDir ))
-    dynamicLinkLibs = glob.glob( os.path.join( MacBinDir, piDir, "*.dylib" ) )
-    for item in dynamicLinkLibs:
-      if os.path.isfile(item) and not os.path.islink(item):
-        #-------------------------------------------------------------------
-        # (A) Copy an ordinary *.dylib file here by changing the name
-        #     to style (3) and set its mode to 0755 (sanity check).
-        #-------------------------------------------------------------------
-        fullName = os.path.basename(item).split('.')
-        # e.g. [ 'libklayout_lay', '0', '26', '1', 'dylib' ]
-        nameStyle3 = fullName[0] + "." + fullName[1] + ".dylib"
-        destPath = os.path.join( targetDirM, piDir, nameStyle3 )
-        shutil.copy2( item, destPath )
-        os.chmod( destPath, 0o0755 )
-        #-------------------------------------------------------------------
-        # (B) Then get inter-library dependencies
-        #     Note that will pull all dependencies and sort them out later
-        #     dropping those which don't have a path entry
-        #-------------------------------------------------------------------
-        otoolCm   = "otool -L %s | grep 'dylib'" % destPath
-        otoolOut  = os.popen( otoolCm ).read()
-        dependDic = DecomposeLibraryDependency(otoolOut)
-        depDicOrdinary.update(dependDic)
-        #-------------------------------------------------------------------
-        # (C) This library goes into the plugin dir
-        #-------------------------------------------------------------------
-        pathDic[nameStyle3] = "@executable_path/" + piDir + "/" + nameStyle3
-
-  '''
-  PrintLibraryDependencyDictionary( depDicOrdinary, pathDic, "Style (3)" )
-  exit()
-  '''
-
-  #----------------------------------------------------------------------------------
-  # (D) Make a symbolic link
-  #        'db_plugins' --slink--> ../MacOS/db_plugins/
-  #     under Frameworks/, which is required for the command line Buddy tools.
-  #
-  #     Ref. https://github.com/KLayout/klayout/issues/460#issuecomment-571803458
-  #
-  #             :
-  #             +-- Frameworks/+
-  #             |              +-- '*.framework'
-  #             |              +-- '*.dylib'
-  #             |              +-- 'db_plugins' --slink--> ../MacOS/db_plugins/
-  #             +-- MacOS/+
-  #             |         +-- 'klayout'
-  #             |         +-- db_plugins/
-  #             |         +-- lay_plugins/
-  #             :
-  #----------------------------------------------------------------------------------
-  os.chdir( targetDirF )
-  os.symlink( "../MacOS/db_plugins/", "./db_plugins" )
-
-
-  print( " [5] Setting and changing the identification names among KLayout's libraries ..." )
-  #-------------------------------------------------------------
-  # [5] Set the identification names for KLayout's libraries
-  #     and make the library aware of the locations of libraries
-  #     on which it depends; that is, inter-library dependency
-  #-------------------------------------------------------------
-  ret = SetChangeIdentificationNameOfDyLib( depDicOrdinary, pathDic )
-  if not ret == 0:
-    msg = "!!! Failed to set and change to new identification names !!!"
-    print(msg)
-    return 1
-
-
-  print( " [6] Copying built executables and resource files ..." )
-  #-------------------------------------------------------------
-  # [6] Copy some known files in source directories to
-  #     relevant target directories
-  #-------------------------------------------------------------
-  os.chdir(ProjectDir)
-  sourceDir0 = "%s/klayout.app/Contents" % MacBinDir
-  sourceDir1 = sourceDir0 + "/MacOS"
-  sourceDir2 = "%s/macbuild/Resources" % ProjectDir
-  sourceDir3 = "%s" % MacBinDir
-
-  tmpfileM = ProjectDir + "/macbuild/Resources/Info.plist.template"
-  keydicM  = { 'exe': 'klayout', 'icon': 'klayout.icns', 'bname': 'klayout', 'ver': Version }
-  plistM   = GenerateInfoPlist( keydicM, tmpfileM )
-  file     = open( targetDir0 + "/Info.plist", "w" )
-  file.write(plistM)
-  file.close()
-
-  shutil.copy2( sourceDir0 + "/PkgInfo",      targetDir0 ) # this file is not mandatory
-  shutil.copy2( sourceDir1 + "/klayout",      targetDirM )
-  shutil.copy2( sourceDir2 + "/klayout.icns", targetDirR )
-
-
-  os.chmod( targetDir0 + "/PkgInfo",      0o0644 )
-  os.chmod( targetDir0 + "/Info.plist",   0o0644 )
-  os.chmod( targetDirM + "/klayout",      0o0755 )
-  os.chmod( targetDirR + "/klayout.icns", 0o0644 )
-
-  buddies = glob.glob( sourceDir3 + "/strm*" )
-  for item in buddies:
-    shutil.copy2( item, targetDirB )
-    buddy = os.path.basename(item)
-    os.chmod( targetDirB + "/" + buddy, 0o0755 )
-
-
-  print( " [7] Setting and changing the identification names of KLayout's libraries in each executable ..." )
-  #-------------------------------------------------------------
-  # [7] Set and change the library identification name(s) of
-  #     different executables
-  #-------------------------------------------------------------
-  os.chdir(ProjectDir)
-  os.chdir(MacPkgDir)
-  klayoutexec = "klayout.app/Contents/MacOS/klayout"
-  ret = SetChangeLibIdentificationName( klayoutexec, "../Frameworks" )
-  if not ret == 0:
+    print("")
+    print( "##### Started deploying libraries and executables for <klayout.app> #####" )
+    print( " [1] Checking the status of working directory ..." )
+    #-------------------------------------------------------------
+    # [1] Check the status of working directory
+    #-------------------------------------------------------------
     os.chdir(ProjectDir)
-    msg = "!!! Failed to set/change library identification name for <%s> !!!"
-    print( msg % klayoutexec, file=sys.stderr )
-    return 1
+    if not DeploymentF and not DeploymentP:
+        return 1
+    if DeploymentF and NonOSStdLang:
+        print( "     WARNING!!! You chose <-y|--deploy> while using non-OS-standard script language.", file=sys.stderr )
+        print( "         Consider using <-Y|--DEPLOY> instead", file=sys.stderr )
+        #return 1
+    if not os.path.isfile(MacBuildLog):
+        print( "!!! Build log file <%s> is not present !!!" % MacBuildLog, file=sys.stderr )
+        return 1
+    if not os.path.isdir(MacBuildDir):
+        print( "!!! Build directory <%s> is not present !!!" % MacBuildDir, file=sys.stderr )
+        return 1
+    if not os.path.isdir(MacBinDir):
+        print( "!!! Binary directory <%s> is not present !!!" % MacBinDir, file=sys.stderr )
+        return 1
 
-  buddies     = glob.glob( "klayout.app/Contents/Buddy/strm*" )
-  macdepQtOpt = ""
-  for buddy in buddies:
-    macdepQtOpt += " -executable=%s" % buddy
-    ret = SetChangeLibIdentificationName( buddy, "../Frameworks" )
+
+    print( " [2] Creating a new empty directory <%s> for deployment ..." % MacPkgDir )
+    #-------------------------------------------------------------
+    # [2] Create a new empty directory for deploying binaries
+    #-------------------------------------------------------------
+    os.chdir(ProjectDir)
+    if os.path.isfile(MacPkgDir):
+        os.remove(MacPkgDir)
+    if os.path.isdir(MacPkgDir):
+        shutil.rmtree(MacPkgDir)
+    os.mkdir(MacPkgDir)
+
+
+    print( " [3] Creating the standard directory structure for 'klayout.app' bundle ..." )
+    #-----------------------------------------------------------------
+    # [3] Create the directory skeleton for "klayout.app" bundle
+    #     and command line buddy tools such as "strm2cif".
+    #     They are stored in the directory structure below.
+    #
+    #    klayout.app/+
+    #                +-- Contents/+
+    #                             +-- Info.plist
+    #                             +-- PkgInfo
+    #                             +-- Resources/+
+    #                             |             +-- 'klayout.icns'
+    #                             +-- Frameworks/+
+    #                             |              +-- '*.framework'
+    #                             |              +-- '*.dylib'
+    #                             |              +-- 'db_plugins' --slink--> ../MacOS/db_plugins/
+    #                             +-- MacOS/+
+    #                             |         +-- 'klayout'
+    #                             |         +-- db_plugins/
+    #                             |         +-- lay_plugins/
+    #                             +-- Buddy/+
+    #                                       +-- 'strm2cif'
+    #                                       +-- 'strm2dxf'
+    #                                       :
+    #                                       +-- 'strmxor'
+    #-----------------------------------------------------------------
+    targetDir0 = "%s/klayout.app/Contents" % AbsMacPkgDir
+    targetDirR = targetDir0 + "/Resources"
+    targetDirF = targetDir0 + "/Frameworks"
+    targetDirM = targetDir0 + "/MacOS"
+    targetDirB = targetDir0 + "/Buddy"
+    os.makedirs(targetDirR)
+    os.makedirs(targetDirF)
+    os.makedirs(targetDirM)
+    os.makedirs(targetDirB)
+
+
+    print( " [4] Copying KLayout's dynamic link libraries to 'Frameworks' ..." )
+    #-------------------------------------------------------------------------------
+    # [4] Copy KLayout's dynamic link libraries to "Frameworks/" and create
+    #     the library dependency dictionary.
+    #     <<< Do this job in "Frameworks/" >>>
+    #
+    # Note:
+    #     KLayout's dynamic link library is built as below:
+    #       (1) libklayout_lay.0.26.1.dylib
+    #       (2) libklayout_lay.0.26.dylib -> libklayout_lay.0.26.1.dylib
+    #       (3) libklayout_lay.0.dylib -> libklayout_lay.0.26.1.dylib
+    #       (4) libklayout_lay.dylib -> libklayout_lay.0.26.1.dylib
+    #     where,
+    #       (1) is an ordinary file with full version number 'major.minor.teeny'
+    #           between "library_name."='libklayout_lay.' and '.dylib'
+    #       (2) is a symbolic link with 'major.minor' version number
+    #       (3) is a symbolic link with 'major' version number
+    #       (4) is a symbolic link without version number number
+    #
+    #     The dynamic linker tries to find a library name in style (3) as shown
+    #     in the example below.
+    #
+    # Example:
+    #   MacBookPro2(1)$ otool -L klayout
+    #   klayout:
+    #       :
+    #       :
+    #     libklayout_tl.0.dylib (compatibility version 0.26.0, current version 0.26.1)
+    #     libklayout_gsi.0.dylib (compatibility version 0.26.0, current version 0.26.1)
+    #     libklayout_db.0.dylib (compatibility version 0.26.0, current version 0.26.1)
+    #       :
+    #-------------------------------------------------------------------------------
+    os.chdir( targetDirF )
+    dynamicLinkLibs = glob.glob( os.path.join( AbsMacBinDir, "*.dylib" ) )
+    depDicOrdinary  = {} # inter-library dependency dictionary
+    pathDic = {} # paths to insert for each library
+    for item in dynamicLinkLibs:
+        if os.path.isfile(item) and not os.path.islink(item):
+            #-------------------------------------------------------------------
+            # (A) Copy an ordinary *.dylib file here by changing the name
+            #     to style (3) and set its mode to 0755 (sanity check).
+            #-------------------------------------------------------------------
+            fullName = os.path.basename(item).split('.')
+            # e.g. [ 'libklayout_lay', '0', '26', '1', 'dylib' ]
+            nameStyle3 = fullName[0] + "." + fullName[1] + ".dylib"
+            shutil.copy2( item, nameStyle3 )
+            os.chmod( nameStyle3, 0o0755 )
+            #-------------------------------------------------------------------
+            # (B) Then get inter-library dependencies
+            #     Note that will pull all dependencies and sort them out later
+            #     dropping those which don't have a path entry
+            #-------------------------------------------------------------------
+            otoolCm   = "otool -L %s | grep dylib" % nameStyle3
+            otoolOut  = os.popen( otoolCm ).read()
+            dependDic = DecomposeLibraryDependency(otoolOut)
+            depDicOrdinary.update(dependDic)
+            #-------------------------------------------------------------------
+            # (C) This library goes into Frameworks, hence record it's path there
+            #-------------------------------------------------------------------
+            pathDic[nameStyle3] = "@executable_path/../Frameworks/" + nameStyle3
+
+    os.chdir(ProjectDir)
+    #-------------------------------------------------------------------
+    # Copy the contents of the plugin directories to a place next to
+    # the application binary
+    #-------------------------------------------------------------------
+    for piDir in [ "db_plugins", "lay_plugins" ]:
+        os.makedirs( os.path.join( targetDirM, piDir ))
+        dynamicLinkLibs = glob.glob( os.path.join( MacBinDir, piDir, "*.dylib" ) )
+        for item in dynamicLinkLibs:
+            if os.path.isfile(item) and not os.path.islink(item):
+                #-------------------------------------------------------------------
+                # (A) Copy an ordinary *.dylib file here by changing the name
+                #     to style (3) and set its mode to 0755 (sanity check).
+                #-------------------------------------------------------------------
+                fullName = os.path.basename(item).split('.')
+                # e.g. [ 'libklayout_lay', '0', '26', '1', 'dylib' ]
+                nameStyle3 = fullName[0] + "." + fullName[1] + ".dylib"
+                destPath = os.path.join( targetDirM, piDir, nameStyle3 )
+                shutil.copy2( item, destPath )
+                os.chmod( destPath, 0o0755 )
+                #-------------------------------------------------------------------
+                # (B) Then get inter-library dependencies
+                #     Note that will pull all dependencies and sort them out later
+                #     dropping those which don't have a path entry
+                #-------------------------------------------------------------------
+                otoolCm   = "otool -L %s | grep 'dylib'" % destPath
+                otoolOut  = os.popen( otoolCm ).read()
+                dependDic = DecomposeLibraryDependency(otoolOut)
+                depDicOrdinary.update(dependDic)
+                #-------------------------------------------------------------------
+                # (C) This library goes into the plugin dir
+                #-------------------------------------------------------------------
+                pathDic[nameStyle3] = "@executable_path/" + piDir + "/" + nameStyle3
+
+    '''
+    PrintLibraryDependencyDictionary( depDicOrdinary, pathDic, "Style (3)" )
+    exit()
+    '''
+
+    #----------------------------------------------------------------------------------
+    # (D) Make a symbolic link
+    #        'db_plugins' --slink--> ../MacOS/db_plugins/
+    #     under Frameworks/, which is required for the command line Buddy tools.
+    #
+    #     Ref. https://github.com/KLayout/klayout/issues/460#issuecomment-571803458
+    #
+    #             :
+    #             +-- Frameworks/+
+    #             |              +-- '*.framework'
+    #             |              +-- '*.dylib'
+    #             |              +-- 'db_plugins' --slink--> ../MacOS/db_plugins/
+    #             +-- MacOS/+
+    #             |         +-- 'klayout'
+    #             |         +-- db_plugins/
+    #             |         +-- lay_plugins/
+    #             :
+    #----------------------------------------------------------------------------------
+    os.chdir( targetDirF )
+    os.symlink( "../MacOS/db_plugins/", "./db_plugins" )
+
+
+    print( " [5] Setting and changing the identification names among KLayout's libraries ..." )
+    #-------------------------------------------------------------
+    # [5] Set the identification names for KLayout's libraries
+    #     and make the library aware of the locations of libraries
+    #     on which it depends; that is, inter-library dependency
+    #-------------------------------------------------------------
+    ret = SetChangeIdentificationNameOfDyLib( depDicOrdinary, pathDic )
     if not ret == 0:
-      os.chdir(ProjectDir)
-      msg = "!!! Failed to set/change library identification name for <%s> !!!"
-      print( msg % buddy, file=sys.stderr )
-      return 1
+        msg = "!!! Failed to set and change to new identification names !!!"
+        print(msg)
+        return 1
 
-  if DeploymentF:
-    print( " [8] Finally, deploying Qt's Frameworks ..." )
+
+    print( " [6] Copying built executables and resource files ..." )
     #-------------------------------------------------------------
-    # [8] Deploy Qt Frameworks
+    # [6] Copy some known files in source directories to
+    #     relevant target directories
     #-------------------------------------------------------------
-    verbose = " -verbose=%d" % DeployVerbose
-    if ModuleQt == 'Qt5MacPorts':
-      deploytool = Qt5MacPorts['deploy']
-      app_bundle = "klayout.app"
-      options    = macdepQtOpt + verbose
-    # To use Qt5 from Homebrew on Catalina...
-    #   in "/usr/local/opt/python/lib/"
-    #         Python.framework -> ../Frameworks/Python.framework/ <=== this symbolic was needed
-    #         pkgconfig/
-    elif ModuleQt == 'Qt5Brew':
-      deploytool = Qt5Brew['deploy']
-      app_bundle = "klayout.app"
-      options    = macdepQtOpt + verbose
-    elif ModuleQt == 'Qt5Ana3':
-      deploytool = Qt5Ana3['deploy']
-      app_bundle = "klayout.app"
-      options    = macdepQtOpt + verbose
+    os.chdir(ProjectDir)
+    sourceDir0 = "%s/klayout.app/Contents" % MacBinDir
+    sourceDir1 = sourceDir0 + "/MacOS"
+    sourceDir2 = "%s/macbuild/Resources" % ProjectDir
+    sourceDir3 = "%s" % MacBinDir
 
-    # Without the following, the plugin cocoa would not be found properly.
-    shutil.copy2( sourceDir2 + "/qt.conf", targetDirM )
-    os.chmod( targetDirM + "/qt.conf",      0o0644 )
+    tmpfileM = ProjectDir + "/macbuild/Resources/Info.plist.template"
+    keydicM  = { 'exe': 'klayout', 'icon': 'klayout.icns', 'bname': 'klayout', 'ver': Version }
+    plistM   = GenerateInfoPlist( keydicM, tmpfileM )
+    file     = open( targetDir0 + "/Info.plist", "w" )
+    file.write(plistM)
+    file.close()
 
+    shutil.copy2( sourceDir0 + "/PkgInfo",      targetDir0 ) # this file is not mandatory
+    shutil.copy2( sourceDir1 + "/klayout",      targetDirM )
+    shutil.copy2( sourceDir2 + "/klayout.icns", targetDirR )
+
+
+    os.chmod( targetDir0 + "/PkgInfo",      0o0644 )
+    os.chmod( targetDir0 + "/Info.plist",   0o0644 )
+    os.chmod( targetDirM + "/klayout",      0o0755 )
+    os.chmod( targetDirR + "/klayout.icns", 0o0644 )
+
+    buddies = glob.glob( sourceDir3 + "/strm*" )
+    for item in buddies:
+        shutil.copy2( item, targetDirB )
+        buddy = os.path.basename(item)
+        os.chmod( targetDirB + "/" + buddy, 0o0755 )
+
+
+    print( " [7] Setting and changing the identification names of KLayout's libraries in each executable ..." )
+    #-------------------------------------------------------------
+    # [7] Set and change the library identification name(s) of
+    #     different executables
+    #-------------------------------------------------------------
     os.chdir(ProjectDir)
     os.chdir(MacPkgDir)
-    command = "%s %s %s" % ( deploytool, app_bundle, options )
-    if subprocess.call( command, shell=True ) != 0:
-      msg = "!!! Failed to deploy applications on OSX/macOS !!!"
-      print( msg, file=sys.stderr )
-      print("")
-      os.chdir(ProjectDir)
-      return 1
+    klayoutexec = "klayout.app/Contents/MacOS/klayout"
+    ret = SetChangeLibIdentificationName( klayoutexec, "../Frameworks" )
+    if not ret == 0:
+        os.chdir(ProjectDir)
+        msg = "!!! Failed to set/change library identification name for <%s> !!!"
+        print( msg % klayoutexec, file=sys.stderr )
+        return 1
 
-    #-------------------------------------------------------------
-    # [9] Special deployment of Python3.7 from Homebrew
-    #-------------------------------------------------------------
-    deploymentPython37HB = (ModulePython == 'Python37Brew')
-    if deploymentPython37HB and NonOSStdLang:
-      from build4mac_util import WalkFrameworkPaths, PerformChanges
+    buddies     = glob.glob( "klayout.app/Contents/Buddy/strm*" )
+    macdepQtOpt = ""
+    for buddy in buddies:
+        macdepQtOpt += " -executable=%s" % buddy
+        ret = SetChangeLibIdentificationName( buddy, "../Frameworks" )
+        if not ret == 0:
+            os.chdir(ProjectDir)
+            msg = "!!! Failed to set/change library identification name for <%s> !!!"
+            print( msg % buddy, file=sys.stderr )
+            return 1
 
-      bundlePath = AbsMacPkgDir + '/klayout.app'
-      bundleExecPathAbs = '%s/Contents/MacOS/' % bundlePath
-      pythonFrameworkPath = '%s/Contents/Frameworks/Python.framework' % bundlePath
+    if DeploymentF:
+        print( " [8] Finally, deploying Qt's Frameworks ..." )
+        #-------------------------------------------------------------
+        # [8] Deploy Qt Frameworks
+        #-------------------------------------------------------------
+        verbose = " -verbose=%d" % DeployVerbose
+        app_bundle = "klayout.app"
+        options = macdepQtOpt + verbose
+        deploytool = parameters['deploy_tool']
 
-      print( "" )
-      print( " [9] Optional deployment of Python from %s ..." % HBPython37FrameworkPath )
-      print( "  [9.1] Copying Python Framework" )
+        # Without the following, the plugin cocoa would not be found properly.
+        shutil.copy2( sourceDir2 + "/qt.conf", targetDirM )
+        os.chmod( targetDirM + "/qt.conf",      0o0644 )
 
-      cmd1 = "rm -rf %s" % pythonFrameworkPath
-      cmd2 = "rsync -a --safe-links %s/ %s" % (HBPython37FrameworkPath, pythonFrameworkPath)
-      cmd3 = "mkdir %s/Versions/3.7/lib/python3.7/site-packages/" % pythonFrameworkPath
-      cmd4 = "cp -RL %s/Versions/3.7/lib/python3.7/site-packages/{pip*,pkg_resources,setuptools*,wheel*} " % \
-              HBPython37FrameworkPath
-      cmd4 += "%s/Versions/3.7/lib/python3.7/site-packages/" % pythonFrameworkPath
-      cmd5 = "rm -rf %s/Versions/3.7/lib/python3.7/test" % pythonFrameworkPath
-      cmd6 = "rm -rf %s/Versions/3.7/Resources" % pythonFrameworkPath
-      cmd7 = "rm -rf %s/Versions/3.7/bin" % pythonFrameworkPath
-
-      shell_commands = list()
-      shell_commands.append(cmd1)
-      shell_commands.append(cmd2)
-      shell_commands.append(cmd3)
-      shell_commands.append(cmd4)
-      shell_commands.append(cmd5)
-      shell_commands.append(cmd6)
-      shell_commands.append(cmd7)
-
-      for command in shell_commands:
+        os.chdir(ProjectDir)
+        os.chdir(MacPkgDir)
+        command = "%s %s %s" % ( deploytool, app_bundle, options )
         if subprocess.call( command, shell=True ) != 0:
-          msg = "command failed: %s"
-          print( msg % command, file=sys.stderr )
-          sys.exit(1)
+            msg = "!!! Failed to deploy applications on OSX/macOS !!!"
+            print( msg, file=sys.stderr )
+            print("")
+            os.chdir(ProjectDir)
+            return 1
 
-      shutil.copy2( sourceDir2 + "/start-console.py", targetDirM )
-      shutil.copy2( sourceDir2 + "/klayout_console", targetDirM )
-      os.chmod( targetDirM + "/klayout_console",      0o0755 )
+        #-----------------------------------------------------------------------------------------------
+        # [9] Special deployment of Python3.8 from Homebrew
+        #     To use Python3.8 from Homebrew on Catalina...
+        #       in "/usr/local/opt/python/lib/"
+        #             Python.framework -> ../Frameworks/Python.framework/ <=== this symbolic was needed
+        #             pkgconfig/
+        #-----------------------------------------------------------------------------------------------
+        deploymentPython38HB = (ModulePython == 'Python38Brew')
+        if deploymentPython38HB and NonOSStdLang:
+            from build4mac_util import WalkFrameworkPaths, PerformChanges
 
-      print("  [9.2] Relinking dylib dependencies inside Python.framework" )
-      print("   [9.2.1] Patching Python Framework" )
-      depdict = WalkFrameworkPaths( pythonFrameworkPath )
-      appPythonFrameworkPath = '@executable_path/../Frameworks/Python.framework/'
-      PerformChanges(depdict, [(HBPython37FrameworkPath, appPythonFrameworkPath, False)], bundleExecPathAbs)
+            pythonHBVer         = "3.8" # 'pinned' to this version as of KLayout version 0.26.7 (2020-09-13)
+            bundlePath          = AbsMacPkgDir + '/klayout.app'
+            bundleExecPathAbs   = '%s/Contents/MacOS/' % bundlePath
+            pythonFrameworkPath = '%s/Contents/Frameworks/Python.framework' % bundlePath
+            testTarget          = '%s/Versions/%s/lib/python%s/test' % (pythonFrameworkPath, pythonHBVer, pythonHBVer)
+            resourceTarget1     = '%s/Versions/%s/Resources' % (pythonFrameworkPath, pythonHBVer)
+            resourceTarget2     = '%s/Resources' % pythonFrameworkPath
+            binTarget           = '%s/Versions/%s/bin' % (pythonFrameworkPath, pythonHBVer)
+            sitepackagesTarget  = '%s/Versions/%s/lib/python%s/site-packages' % (pythonFrameworkPath, pythonHBVer, pythonHBVer)
+            sitepackagesSource  = '%s/Versions/%s/lib/python%s/site-packages' % (HBPython38FrameworkPath, pythonHBVer, pythonHBVer)
 
-      print("   [9.2.2] Patching /usr/local/opt/ libs")
-      usrLocalPath = '/usr/local/opt/'
-      appUsrLocalPath = '@executable_path/../Frameworks/'
-      replacePairs = [(usrLocalPath, appUsrLocalPath, True)]
-      depdict = WalkFrameworkPaths(pythonFrameworkPath, search_path_filter=r'\t+/usr/local/(opt|Cellar)')
-      PerformChanges(depdict, replacePairs, bundleExecPathAbs)
+            print( "" )
+            print( " [9] Optional deployment of Python from %s ..." % HBPython38FrameworkPath )
+            print( "  [9.1] Copying Python Framework" )
 
-      print("   [9.2.3] Patching openssl, gdbm, readline, sqlite, tcl-tk, xz")
-      usrLocalPath = '/usr/local/opt'
-      appUsrLocalPath = '@executable_path/../Frameworks/'
-      replacePairs = [(usrLocalPath, appUsrLocalPath, True)]
-      replacePairs.extend([(openssl_version, '@executable_path/../Frameworks/openssl', True)
-        for openssl_version in glob.glob('/usr/local/Cellar/openssl/*')])
-      depdict = WalkFrameworkPaths([pythonFrameworkPath + '/../openssl',
-                                    pythonFrameworkPath + '/../gdbm',
-                                    pythonFrameworkPath + '/../readline',
-                                    pythonFrameworkPath + '/../sqlite',
-                                    pythonFrameworkPath + '/../tcl-tk',
-                                    pythonFrameworkPath + '/../xz'], search_path_filter=r'\t+/usr/local/(opt|Cellar)')
+            cmd01 = "rm -rf %s" % pythonFrameworkPath
+            cmd02 = "rsync -a --safe-links %s/ %s" % (HBPython38FrameworkPath, pythonFrameworkPath)
 
-      PerformChanges(depdict, replacePairs, bundleExecPathAbs)
+            cmd03 = "rm -rf %s" % testTarget
+            cmd04 = "rm -rf %s" % resourceTarget1
+            cmd05 = "unlink %s" % resourceTarget2
+            cmd06 = "rm -rf %s" % binTarget
 
-      print("  [9.3] Relinking dylib dependencies for klayout")
-      klayoutPath = bundleExecPathAbs
-      depdict = WalkFrameworkPaths(klayoutPath, filter_regex=r'klayout$')
-      PerformChanges(depdict, [(HBPython37FrameworkPath, appPythonFrameworkPath, False)], bundleExecPathAbs)
+            cmd07 = "mkdir %s" % sitepackagesTarget
+            cmd08 = "cp -RL %s/{pip*,pkg_resources,setuptools*,wheel*} %s" % (sitepackagesSource, sitepackagesTarget)
 
-      libKlayoutPath = bundleExecPathAbs + '../Frameworks'
-      depdict = WalkFrameworkPaths(libKlayoutPath, filter_regex=r'libklayout')
-      PerformChanges(depdict, [(HBPython37FrameworkPath, appPythonFrameworkPath, False)], bundleExecPathAbs)
+            shell_commands = list()
+            shell_commands.append(cmd01)
+            shell_commands.append(cmd02)
+            shell_commands.append(cmd03)
+            shell_commands.append(cmd04)
+            shell_commands.append(cmd05)
+            shell_commands.append(cmd06)
+            shell_commands.append(cmd07)
+            shell_commands.append(cmd08)
 
-      print("  [9.4] Patching site.py, pip/, and distutils/")
-      site_module = "%s/Versions/3.7/lib/python3.7/site.py" % pythonFrameworkPath
-      with open(site_module, 'r') as site:
-        buf = site.readlines()
-      with open(site_module, 'w') as site:
-        import re
-        for line in buf:
-          # This will fool pip into thinking it's inside a virtual environment
-          # and install new packates to the correct site-packages
-          if re.match("^PREFIXES", line) is not None:
-            line = line + "sys.real_prefix = sys.prefix\n"
-          # do not allow installation in the user folder.
-          if re.match("^ENABLE_USER_SITE", line) is not None:
-            line = "ENABLE_USER_SITE = False\n"
-          site.write(line)
+            for command in shell_commands:
+                if subprocess.call( command, shell=True ) != 0:
+                    msg = "command failed: %s"
+                    print( msg % command, file=sys.stderr )
+                    sys.exit(1)
 
-      pip_module = "%s/Versions/3.7/lib/python3.7/site-packages/pip/__init__.py" % pythonFrameworkPath
-      with open(pip_module, 'r') as pip:
-        buf = pip.readlines()
-      with open(pip_module, 'w') as pip:
-        import re
-        for line in buf:
-          # this will reject user's configuration of pip, forcing the isolated mode
-          line = re.sub("return isolated$", "return isolated or True", line)
-          pip.write(line)
+            shutil.copy2( sourceDir2 + "/start-console.py", targetDirM )
+            shutil.copy2( sourceDir2 + "/klayout_console",  targetDirM )
+            os.chmod( targetDirM + "/start-console.py", 0o0755 )
+            os.chmod( targetDirM + "/klayout_console",  0o0755 )
 
-      distutilsconfig = "%s/Versions/3.7/lib/python3.7/distutils/distutils.cfg" % pythonFrameworkPath
-      with open(distutilsconfig, 'r') as file:
-        buf = file.readlines()
-      with open(distutilsconfig, 'w') as file:
-        import re
-        for line in buf:
-          # This will cause all packages to be installed to sys.prefix
-          if re.match('prefix=', line) is not None:
-            continue
-          file.write(line)
+            print("  [9.2] Relinking dylib dependencies inside Python.framework" )
+            print("   [9.2.1] Patching Python Framework" )
+            depdict = WalkFrameworkPaths( pythonFrameworkPath )
+            appPythonFrameworkPath = '@executable_path/../Frameworks/Python.framework/'
+            PerformChanges(depdict, [(HBPython38FrameworkPath, appPythonFrameworkPath, False)], bundleExecPathAbs)
 
-    #-------------------------------------------------------------
-    # [10] Special deployment of Ruby2.6 from Homebrew?
-    #-------------------------------------------------------------
-    deploymentRuby26HB = (ModuleRuby == 'Ruby27Brew')
-    if deploymentRuby26HB and NonOSStdLang:
+            print("   [9.2.2] Patching /usr/local/opt/ libs")
+            usrLocalPath = '/usr/local/opt/'
+            appUsrLocalPath = '@executable_path/../Frameworks/'
+            replacePairs = [(usrLocalPath, appUsrLocalPath, True)]
+            depdict = WalkFrameworkPaths(pythonFrameworkPath, search_path_filter=r'\t+/usr/local/(opt|Cellar)')
+            PerformChanges(depdict, replacePairs, bundleExecPathAbs)
 
-      print( "" )
-      print( " [10] You have reached optional deployment of Ruby from %s ..." % HBRuby27Path )
-      print( "   [!!!] Sorry, the deployed package will not work properly since deployment of" )
-      print( "         Ruby2.6 from Homebrew is not yet supported." )
-      print( "         Since you have Homebrew development environment, there two options:" )
-      print( "           (1) Retry to make a package with '-Y|--DEPLOY' option." )
-      print( "               This will not deploy any of Qt5, Python, and Ruby from Homebrew." )
-      print( "               Instead, the package will directly use those Frameworks and libraries" )
-      print( "               in your Homebrew environment." )
-      print( "           (2) Rebuild KLayout with '-r|--ruby <nil|Sys>' option depending on your preference." )
-      print( "" )
+            print("   [9.2.3] Patching openssl@1.1, gdbm, readline, sqlite, xz")
+            usrLocalPath = '/usr/local/opt'
+            appUsrLocalPath = '@executable_path/../Frameworks/'
+            replacePairs = [(usrLocalPath, appUsrLocalPath, True)]
+            replacePairs.extend([(openssl_version, '@executable_path/../Frameworks/openssl@1.1', True)
+                for openssl_version in glob.glob('/usr/local/Cellar/openssl@1.1/*')])
+            depdict = WalkFrameworkPaths([pythonFrameworkPath + '/../openssl@1.1',
+                                                                        pythonFrameworkPath + '/../gdbm',
+                                                                        pythonFrameworkPath + '/../readline',
+                                                                        pythonFrameworkPath + '/../sqlite',
+                                                                        pythonFrameworkPath + '/../xz'], search_path_filter=r'\t+/usr/local/(opt|Cellar)')
 
-  else:
-    print( " [8] Skipped deploying Qt's Frameworks and optional Python/Ruby Frameworks..." )
-  print( "##### Finished deploying libraries and executables for <klayout.app> #####" )
-  print("")
-  os.chdir(ProjectDir)
-  return 0
+            PerformChanges(depdict, replacePairs, bundleExecPathAbs)
+
+            print("  [9.3] Relinking dylib dependencies for klayout")
+            klayoutPath = bundleExecPathAbs
+            depdict = WalkFrameworkPaths(klayoutPath, filter_regex=r'klayout$')
+            PerformChanges(depdict, [(HBPython38FrameworkPath, appPythonFrameworkPath, False)], bundleExecPathAbs)
+
+            libKlayoutPath = bundleExecPathAbs + '../Frameworks'
+            depdict = WalkFrameworkPaths(libKlayoutPath, filter_regex=r'libklayout')
+            PerformChanges(depdict, [(HBPython38FrameworkPath, appPythonFrameworkPath, False)], bundleExecPathAbs)
+
+            print("  [9.4] Patching site.py, pip/, and distutils/")
+            site_module = "%s/Versions/%s/lib/python%s/site.py" % (pythonFrameworkPath, pythonHBVer, pythonHBVer)
+            with open(site_module, 'r') as site:
+                buf = site.readlines()
+            with open(site_module, 'w') as site:
+                import re
+                for line in buf:
+                    # This will fool pip into thinking it's inside a virtual environment
+                    # and install new packages to the correct site-packages
+                    if re.match("^PREFIXES", line) is not None:
+                        line = line + "sys.real_prefix = sys.prefix\n"
+                    # do not allow installation in the user folder.
+                    if re.match("^ENABLE_USER_SITE", line) is not None:
+                        line = "ENABLE_USER_SITE = False\n"
+                    site.write(line)
+
+            #----------------------------------------------------------------------------------
+            # Typical usage of 'pip' after installation of the DMG package
+            #
+            # $ /Applications/klayout.app/Contents/MacOS/start-console.py
+            # Warning: Populating font family aliases took 195 ms. Replace uses of missing font\
+            # family "Monospace" with one that exists to avoid this cost.
+            # Python 3.7.8 (default, Jul  4 2020, 10:17:17)
+            # [Clang 11.0.3 (clang-1103.0.32.62)] on darwin
+            # Type "help", "copyright", "credits" or "license" for more information.
+            # (KLayout Python Console)
+            # >>> import pip
+            # >>> pip.main( ['install', 'numpy'] )
+            # >>> pip.main( ['install', 'scipy'] )
+            # >>> pip.main( ['install', 'pandas'] )
+            # >>> pip.main( ['install', 'matplotlib'] )
+            #----------------------------------------------------------------------------------
+            pip_module = "%s/Versions/%s/lib/python%s/site-packages/pip/__init__.py" % \
+                                     (pythonFrameworkPath, pythonHBVer, pythonHBVer)
+            with open(pip_module, 'r') as pip:
+                buf = pip.readlines()
+            with open(pip_module, 'w') as pip:
+                import re
+                for line in buf:
+                    # this will reject user's configuration of pip, forcing the isolated mode
+                    line = re.sub("return isolated$", "return isolated or True", line)
+                    pip.write(line)
+
+            distutilsconfig = "%s/Versions/%s/lib/python%s/distutils/distutils.cfg" % \
+                                                (pythonFrameworkPath, pythonHBVer, pythonHBVer)
+            with open(distutilsconfig, 'r') as file:
+                buf = file.readlines()
+            with open(distutilsconfig, 'w') as file:
+                import re
+                for line in buf:
+                    # This will cause all packages to be installed to sys.prefix
+                    if re.match('prefix=', line) is not None:
+                        continue
+                    file.write(line)
+
+        #-------------------------------------------------------------
+        # [10] Special deployment of Ruby2.7 from Homebrew?
+        #-------------------------------------------------------------
+        deploymentRuby26HB = (ModuleRuby == 'Ruby27Brew')
+        if deploymentRuby26HB and NonOSStdLang:
+
+            print( "" )
+            print( " [10] You have reached optional deployment of Ruby from %s ..." % HBRuby27Path )
+            print( "   [!!!] Sorry, the deployed package will not work properly since deployment of" )
+            print( "         Ruby2.7 from Homebrew is not yet supported." )
+            print( "         Since you have Homebrew development environment, there two options:" )
+            print( "           (1) Retry to make a package with '-Y|--DEPLOY' option." )
+            print( "               This will not deploy any of Qt5, Python, and Ruby from Homebrew." )
+            print( "               Instead, the package will directly use those Frameworks and libraries" )
+            print( "               in your Homebrew environment." )
+            print( "           (2) Rebuild KLayout with '-r|--ruby <nil|Sys>' option depending on your preference." )
+            print( "" )
+
+    else:
+        print( " [8] Skipped deploying Qt's Frameworks and optional Python/Ruby Frameworks..." )
+    print( "##### Finished deploying libraries and executables for <klayout.app> #####" )
+    print("")
+    os.chdir(ProjectDir)
+    return 0
 
 #------------------------------------------------------------------------------
 ## The main function
 #------------------------------------------------------------------------------
 def main():
-  SetGlobals()
-  ParseCommandLineArguments()
+    import pprint
+    pp = pprint.PrettyPrinter(indent=4)
+    config = get_default_config()
+    parse_cli_args(config)
+    #----------------------------------------------------------
+    # [The main build stage]
+    #----------------------------------------------------------
+    parameters = get_build_parameters(config)
+    pp.pprint(parameters)
 
-  #----------------------------------------------------------
-  # [The main build stage]
-  #----------------------------------------------------------
-  ret = RunMainBuildBash()
-  if not DeploymentF and not DeploymentP:
-    if not ret == 0:
-      sys.exit(1)
-  else:
-    #----------------------------------------------------------
-    # [The deployment stage]
-    #   Deployment of dynamic link libraries, executables and
-    #   resources to make the main "klayout.app" bundle
-    #----------------------------------------------------------
-    ret = DeployBinariesForBundle()
-    if not ret == 0:
-      sys.exit(1)
+    if not config['DeploymentF'] and not config['DeploymentP']:
+        ret = run_build_command(parameters)
+        pp.pprint(config)
+        if not ret == 0:
+            sys.exit(1)
+    else:
+        #----------------------------------------------------------
+        # [The deployment stage]
+        #   Deployment of dynamic link libraries, executables and
+        #   resources to make the main "klayout.app" bundle
+        #----------------------------------------------------------
+        ret = DeployBinariesForBundle(config, parameters)
+        if not ret == 0:
+            sys.exit(1)
 
 #===================================================================================
 if __name__ == "__main__":
-  main()
+    main()
 
 #---------------
 # End of file
diff --git a/macbuild/build4mac_env.py b/macbuild/build4mac_env.py
index 033e574d9..89b9f7690 100755
--- a/macbuild/build4mac_env.py
+++ b/macbuild/build4mac_env.py
@@ -104,9 +104,10 @@ RubyMojave      = { 'exe': '/System/Library/Frameworks/Ruby.framework/Versions/2
 #   !!! Catalina does not allow to hack the "/System" directory; it's READ ONLY even for the super user!
 #       Hence, we need to refer to the Ruby header file in "Xcode.app" directly.
 # [Key Type Name] = 'Sys'
-CatalinaSDK = "/Applications/Xcode.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX10.15.sdk"
+CatalinaSDK = "/Applications/Xcode.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX11.0.sdk"
 RubyCatalina    = { 'exe': '/System/Library/Frameworks/Ruby.framework/Versions/2.6/usr/bin/ruby',
                     'inc': '%s/System/Library/Frameworks/Ruby.framework/Headers' % CatalinaSDK,
+                    'inc2': '%s/System/Library/Frameworks/Ruby.framework/Headers/ruby' % CatalinaSDK,
                     'lib': '/System/Library/Frameworks/Ruby.framework/Versions/2.6/usr/lib/libruby.dylib'
                   }
 
@@ -154,7 +155,7 @@ RubyDictionary  = { 'nil'           : None,
 #-----------------------------------------------------
 PythonNil = [ 'nil' ]
 PythonSys = [ 'PythonElCapitan', 'PythonSierra', 'PythonHighSierra', 'PythonMojave', 'PythonCatalina' ]
-PythonExt = [ 'Python37MacPorts', 'Python37Brew', 'PythonAnaconda3' ]
+PythonExt = [ 'Python38MacPorts', 'Python38Brew', 'PythonAnaconda3' ]
 Pythons   = PythonNil + PythonSys + PythonExt
 
 #-----------------------------------------------------
@@ -204,30 +205,45 @@ PythonCatalina  = { 'exe': '/System/Library/Frameworks/Python.framework/Versions
                     'lib': '/System/Library/Frameworks/Python.framework/Versions/2.7/lib/libpython2.7.dylib'
                   }
 
-# Python 3.7 from MacPorts (https://www.macports.org/) *+*+*+ EXPERIMENTAL *+*+*+
-#   install with 'sudo port install python37'
-# [Key Type Name] = 'MP37'
-Python37MacPorts= { 'exe': '/opt/local/Library/Frameworks/Python.framework/Versions/3.7/bin/python3.7m',
-                    'inc': '/opt/local/Library/Frameworks/Python.framework/Versions/3.7/include/python3.7m',
-                    'lib': '/opt/local/Library/Frameworks/Python.framework/Versions/3.7/lib/libpython3.7m.dylib'
+# Python 3.8 from MacPorts (https://www.macports.org/) *+*+*+ EXPERIMENTAL *+*+*+
+#   install with 'sudo port install python38'
+# [Key Type Name] = 'MP38'
+Python38MacPorts= { 'exe': '/opt/local/Library/Frameworks/Python.framework/Versions/3.8/bin/python3.8',
+                    'inc': '/opt/local/Library/Frameworks/Python.framework/Versions/3.8/include/python3.8',
+                    'lib': '/opt/local/Library/Frameworks/Python.framework/Versions/3.8/lib/libpython3.8.dylib'
                   }
 
-# Python 3.7 from Homebrew *+*+*+ EXPERIMENTAL *+*+*+
+# Python 3.8 from Homebrew *+*+*+ EXPERIMENTAL *+*+*+
 #   install with 'brew install python'
-# [Key Type Name] = 'HB37'
-HBPython37FrameworkPath = '/usr/local/opt/python3/Frameworks/Python.framework'
-Python37Brew    = { 'exe': '%s/Versions/3.7/bin/python3.7m' % HBPython37FrameworkPath,
-                    'inc': '%s/Versions/3.7/include/python3.7m' % HBPython37FrameworkPath,
-                    'lib': '%s/Versions/3.7/lib/libpython3.7m.dylib' % HBPython37FrameworkPath
+# [Key Type Name] = 'HB38'
+HBPython38FrameworkPath = '/usr/local/opt/python3/Frameworks/Python.framework'
+Python38Brew    = { 'exe': '%s/Versions/3.8/bin/python3.8' % HBPython38FrameworkPath,
+                    'inc': '%s/Versions/3.8/include/python3.8' % HBPython38FrameworkPath,
+                    'lib': '%s/Versions/3.8/lib/libpython3.8.dylib' % HBPython38FrameworkPath
                   }
 
-# Python 3.7 bundled with anaconda3 installed under /Applications/anaconda3/ *+*+*+ EXPERIMENTAL *+*+*+
+# # Latest Python from Homebrew *+*+*+ EXPERIMENTAL *+*+*+
+# #   install with 'brew install python'
+# # [Key Type Name] = 'HBAuto'
+
+# import glob
+# # In my system, there are four candidates: (python, python3, python@3, python@3.8)
+# # Hard to tell which is going to be available to the user. Picking the last one
+# HBAutoFrameworkPath = glob.glob("/usr/local/opt/python*/Frameworks/Python.framework/")[-1]
+# # expand 3* into _py_version, there should be only one, but I am taking no chances.
+# HBAutoFrameworkVersionPath, _py_version = os.path.split(glob.glob("%s/Versions/3*" % HBAutoFrameworkPath)[0])
+# PythonAutoBrew = {  'exe': '%s/bin/python%s' % (HBAutoFrameworkVersionPath, _py_version),
+#                     'inc': '%s/include/python%s' % (HBAutoFrameworkVersionPath, _py_version),
+#                     'lib': glob.glob("%s/lib/*.dylib" % HBAutoFrameworkVersionPath)[0]
+#                   }
+
+# Python 3.8 bundled with anaconda3 installed under /Applications/anaconda3/ *+*+*+ EXPERIMENTAL *+*+*+
 # The standard installation deploys the tool under $HOME/opt/anaconda3/.
 # If so, you need to make a symbolic link: /Applications/anaconda3 ---> $HOME/opt/anaconda3/
 # [Key Type Name] = 'Ana3'
-PythonAnaconda3 = { 'exe': '/Applications/anaconda3/bin/python3.7m',
-                    'inc': '/Applications/anaconda3/include/python3.7m',
-                    'lib': '/Applications/anaconda3/lib/libpython3.7m.dylib'
+PythonAnaconda3 = { 'exe': '/Applications/anaconda3/bin/python3.8',
+                    'inc': '/Applications/anaconda3/include/python3.8',
+                    'lib': '/Applications/anaconda3/lib/libpython3.8.dylib'
                   }
 
 # Consolidated dictionary kit for Python
@@ -237,8 +253,8 @@ PythonDictionary= { 'nil'             : None,
                     'PythonHighSierra': PythonHighSierra,
                     'PythonMojave'    : PythonMojave,
                     'PythonCatalina'  : PythonCatalina,
-                    'Python37MacPorts': Python37MacPorts,
-                    'Python37Brew'    : Python37Brew,
+                    'Python38MacPorts': Python38MacPorts,
+                    'Python38Brew'    : Python38Brew,
                     'PythonAnaconda3' : PythonAnaconda3
                   }
 
diff --git a/macbuild/build4mac_util.py b/macbuild/build4mac_util.py
index ea682fe21..0c6d0d5cc 100755
--- a/macbuild/build4mac_util.py
+++ b/macbuild/build4mac_util.py
@@ -1,7 +1,7 @@
 #! /usr/bin/env python
 # -*- coding: utf-8 -*-
 
-#===============================================================================
+#========================================================================================
 # File: "macbuild/build4mac_util.py"
 #
 # Here are utility functions and classes ...
@@ -9,7 +9,7 @@
 #  version 0.26.1 or later on different Apple Mac OSX platforms.
 #
 # This file is imported by 'build4mac.py' script.
-#===============================================================================
+#========================================================================================
 from __future__ import print_function  # to use print() of Python 3 in Python >= 2.7
 import sys
 import os
@@ -18,14 +18,14 @@ import string
 import subprocess
 import shutil
 
-#-------------------------------------------------------------------------------
+#----------------------------------------------------------------------------------------
 ## To import global dictionaries of different modules
-#-------------------------------------------------------------------------------
+#----------------------------------------------------------------------------------------
 mydir = os.path.dirname(os.path.abspath(__file__))
 sys.path.append( mydir )
 from build4mac_env  import *
 
-#------------------------------------------------------------------------------
+#----------------------------------------------------------------------------------------
 ## To decompose strings obtained by 'otool -L <*.dylib>' command and to
 #  generate a dictionary of KLayout's inter-library dependency.
 #
@@ -41,81 +41,81 @@ from build4mac_env  import *
 #      :
 #
 # @return a dictionary
-#------------------------------------------------------------------------------
+#----------------------------------------------------------------------------------------
 def DecomposeLibraryDependency( depstr ):
-  alllines   = depstr.split('\n')
-  numlines   = len(alllines)
-  dependent  = alllines[0].split(':')[0].strip()
-  supporters = []
-  for line in alllines[1:]:
-    supporter = line.strip().split(' ')[0].strip()
-    if not supporter == '':
-      supporters.append(supporter)
-  return { dependent: supporters }
+    alllines   = depstr.split('\n')
+    numlines   = len(alllines)
+    dependent  = alllines[0].split(':')[0].strip()
+    supporters = []
+    for line in alllines[1:]:
+        supporter = line.strip().split(' ')[0].strip()
+        if not supporter == '':
+            supporters.append(supporter)
+    return { dependent: supporters }
 
-#------------------------------------------------------------------------------
+#----------------------------------------------------------------------------------------
 ## To print the contents of a library dependency dictionary
 #
 # @param[in] depdic  dictionary
 # @param[in] pathdic path dictionary
 # @param[in] namedic dictionary name
-#------------------------------------------------------------------------------
+#----------------------------------------------------------------------------------------
 def PrintLibraryDependencyDictionary( depdic, pathdic, namedic ):
-  keys = depdic.keys()
-  print("")
-  print("##### Contents of <%s> #####:" % namedic )
-  for key in keys:
-    supporters = depdic[key]
-    keyName = os.path.basename(key)
-    print( " %s: (%s)" % (key, pathdic[keyName]) )
-    for item in supporters:
-      itemName = os.path.basename(item)
-      if itemName != keyName and (itemName in pathdic):
-        print( "    %s (%s)" % (item, pathdic[itemName]) )
+    keys = depdic.keys()
+    print("")
+    print("##### Contents of <%s> #####:" % namedic )
+    for key in keys:
+        supporters = depdic[key]
+        keyName = os.path.basename(key)
+        print( " %s: (%s)" % (key, pathdic[keyName]) )
+        for item in supporters:
+            itemName = os.path.basename(item)
+            if itemName != keyName and (itemName in pathdic):
+                print( "    %s (%s)" % (item, pathdic[itemName]) )
 
-#------------------------------------------------------------------------------
+#----------------------------------------------------------------------------------------
 ## To set and change identification name of KLayout's dylib
 #
 # @param[in] libdic  inter-library dependency dictionary
 #
 # @return 0 on success; non-zero on failure
-#------------------------------------------------------------------------------
+#----------------------------------------------------------------------------------------
 def SetChangeIdentificationNameOfDyLib( libdic, pathDic ):
-  cmdNameId     = XcodeToolChain['nameID']
-  cmdNameChg    = XcodeToolChain['nameCH']
-  dependentLibs = libdic.keys()
+    cmdNameId     = XcodeToolChain['nameID']
+    cmdNameChg    = XcodeToolChain['nameCH']
+    dependentLibs = libdic.keys()
 
-  for lib in dependentLibs:
-    #-----------------------------------------------------------
-    # [1] Set the identification name of each dependent library
-    #-----------------------------------------------------------
-    nameOld = "%s" % lib
-    libName = os.path.basename(lib)
-    nameNew = pathDic[libName]
-    command = "%s %s %s" % ( cmdNameId, nameNew, nameOld )
-    if subprocess.call( command, shell=True ) != 0:
-      msg = "!!! Failed to set the new identification name to <%s> !!!"
-      print( msg % lib, file=sys.stderr )
-      return 1
-
-    #-------------------------------------------------------------------------
-    # [2] Make the library aware of the new identifications of all supporters
-    #-------------------------------------------------------------------------
-    supporters = libdic[lib]
-    for sup in supporters:
-      supName = os.path.basename(sup)
-      if libName != supName and (supName in pathDic):
-        nameOld = "%s" % sup
-        nameNew = pathDic[supName]
-        command = "%s %s %s %s" % ( cmdNameChg, nameOld, nameNew, lib )
+    for lib in dependentLibs:
+        #-----------------------------------------------------------
+        # [1] Set the identification name of each dependent library
+        #-----------------------------------------------------------
+        nameOld = "%s" % lib
+        libName = os.path.basename(lib)
+        nameNew = pathDic[libName]
+        command = "%s %s %s" % ( cmdNameId, nameNew, nameOld )
         if subprocess.call( command, shell=True ) != 0:
-          msg = "!!! Failed to make the library aware of the new identification name <%s> of supporter <%s> !!!"
-          print( msg % (nameNew, sup), file=sys.stderr )
-          return 1
-  # for-lib
-  return 0
+            msg = "!!! Failed to set the new identification name to <%s> !!!"
+            print( msg % lib, file=sys.stderr )
+            return 1
 
-#------------------------------------------------------------------------------
+        #-------------------------------------------------------------------------
+        # [2] Make the library aware of the new identifications of all supporters
+        #-------------------------------------------------------------------------
+        supporters = libdic[lib]
+        for sup in supporters:
+            supName = os.path.basename(sup)
+            if libName != supName and (supName in pathDic):
+                nameOld = "%s" % sup
+                nameNew = pathDic[supName]
+                command = "%s %s %s %s" % ( cmdNameChg, nameOld, nameNew, lib )
+                if subprocess.call( command, shell=True ) != 0:
+                    msg = "!!! Failed to make the library aware of the new identification name <%s> of supporter <%s> !!!"
+                    print( msg % (nameNew, sup), file=sys.stderr )
+                    return 1
+    # for-lib
+    return 0
+
+#----------------------------------------------------------------------------------------
 ## To set the identification names of KLayout's libraries to an executable
 #     and make the application aware of the library locations
 #
@@ -146,259 +146,321 @@ def SetChangeIdentificationNameOfDyLib( libdic, pathDic ):
 #                                       +-- 'strmxor'
 #
 # @return 0 on success; non-zero on failure
-#------------------------------------------------------------------------------
+#----------------------------------------------------------------------------------------
 def SetChangeLibIdentificationName( executable, relativedir ):
-  cmdNameId  = XcodeToolChain['nameID']
-  cmdNameChg = XcodeToolChain['nameCH']
-  otoolCm    = "otool -L %s | grep libklayout" % executable
-  otoolOut   = os.popen( otoolCm ).read()
-  exedepdic  = DecomposeLibraryDependency( executable + ":\n" + otoolOut )
-  keys       = exedepdic.keys()
-  deplibs    = exedepdic[ list(keys)[0] ]
+    cmdNameId  = XcodeToolChain['nameID']
+    cmdNameChg = XcodeToolChain['nameCH']
+    otoolCm    = "otool -L %s | grep libklayout" % executable
+    otoolOut   = os.popen( otoolCm ).read()
+    exedepdic  = DecomposeLibraryDependency( executable + ":\n" + otoolOut )
+    keys       = exedepdic.keys()
+    deplibs    = exedepdic[ list(keys)[0] ]
 
-  for lib in deplibs:
-    #-----------------------------------------------------------
-    # [1] Set the identification names for the library
-    #-----------------------------------------------------------
-    nameOld = "klayout.app/Contents/Frameworks/%s" % lib
-    nameNew = "@executable_path/%s/%s"  % ( relativedir, lib )
-    command = "%s %s %s" % ( cmdNameId, nameNew, nameOld )
-    if subprocess.call( command, shell=True ) != 0:
-      msg = "!!! Failed to set the new identification name to <%s> !!!"
-      print( msg % lib, file=sys.stderr )
-      return 1
-
-    #-----------------------------------------------------------
-    # [2] Make the application aware of the new identification
-    #-----------------------------------------------------------
-    nameOld = "%s" % lib
-    nameNew = "@executable_path/%s/%s"  % ( relativedir, lib )
-    command = "%s %s %s %s" % ( cmdNameChg, nameOld, nameNew, executable )
-    if subprocess.call( command, shell=True ) != 0:
-      msg = "!!! Failed to make the application aware of the new identification name <%s> !!!"
-      print( msg % nameNew, file=sys.stderr )
-      return 1
-  # for-lib
-  return 0
-
-def WalkLibDependencyTree( dylibPath, depth=0, filter_regex=r'\t+/usr/local/opt'):
-  NOTHINGTODO = []  # return empty list if nothing to do.
-  cmdNameId  = XcodeToolChain['nameID']
-  cmdNameChg = XcodeToolChain['nameCH']
-  otoolCm    = 'otool -L %s | grep -E "%s"' % (dylibPath, filter_regex)
-  otoolOut   = os.popen( otoolCm ).read()
-  exedepdic  = DecomposeLibraryDependency( dylibPath + ":\n" + otoolOut )
-  keys       = exedepdic.keys()
-  deplibs    = exedepdic[ list(keys)[0] ]
-
-  if depth < 5:
-    if len(deplibs) > 0:
-      for idx, lib in enumerate(deplibs):
-        lib = str(lib)
-        if lib != list(keys)[0]:
-          deplibs[idx] = WalkLibDependencyTree(lib, depth+1, filter_regex)
-    if depth == 0:
-      return deplibs
-    return exedepdic
-  else:
-    raise RuntimeError("Exceeded maximum recursion depth.")
-
-def WalkFrameworkPaths(frameworkPaths, filter_regex=r'\.(so|dylib)$', search_path_filter=r'\t+/usr/local/opt'):
-
-  if isinstance(frameworkPaths, str):
-    frameworkPathsIter = [frameworkPaths]
-  else:
-    frameworkPathsIter = frameworkPaths
-
-  dependency_dict = dict()
-
-  for frameworkPath in frameworkPathsIter:
-    # print("Calling:", 'find %s -type f | grep -E "%s"' % (frameworkPath, filter_regex))
-    find_grep_results = os.popen('find %s -type f | grep -E "%s"' % (frameworkPath, filter_regex)).read().split('\n')
-    framework_files = filter(lambda x: x != '',
-                          map(lambda x: x.strip(),
-                                find_grep_results))
-
-    dependency_dict[frameworkPath] = list()
-    for idx, file in enumerate(framework_files):
-      dict_file = {file: WalkLibDependencyTree(file, filter_regex=search_path_filter)}
-      dependency_dict[frameworkPath].append(dict_file)
-  return dependency_dict
-
-def WalkDictTree(dependencyDict, visited_files):
-  libNameChanges = list()
-  for lib, dependencies in dependencyDict.items():
-    if lib in visited_files:
-      continue
-
-    dependency_list = list()
-    if isinstance(dependencies, list):
-      for deplib in dependencies:
-        if isinstance(deplib, str):
-          dependency_list.append(deplib)
-          if deplib not in visited_files:
-            visited_files.append(deplib)
-        elif isinstance(deplib, dict):
-          dependency_list.append(next(iter(deplib)))
-          libNameChanges.extend(WalkDictTree(deplib, visited_files))
-        else:
-          #raise RuntimeError("Unexpected value: %s" % deplib)
-          pass
-    else:
-      raise RuntimeError("Unexpected value: %s" % dependencies)
-    if len(dependency_list) > 0:
-      libNameChanges.append((lib, dependency_list))
-    else:
-      libNameChanges.append((lib, ))
-    visited_files.append(lib)
-  return libNameChanges
-
-
-def FindFramework(path, root_path):
-  relPath = os.path.relpath(path, root_path)
-  return os.path.join(root_path, relPath.split(os.sep)[0])
-def ResolveExecutablePath(path, executable_path):
-  """ Transforms @executable_path into executable_path"""
-  p = path.replace("@executable_path", "/%s/" % executable_path)
-  return p
-
-def DetectChanges(frameworkDependencyDict):
-  visited_files = list()
-  libNameChanges = list()
-  for framework, libraries in frameworkDependencyDict.items():
-    for libraryDict in libraries:
-      libNameChanges.extend(WalkDictTree(libraryDict, visited_files))
-  # Changes are stored in libNameChanges in the form of ('lib.dylib', ['dep1.dylib', ...])
-
-  return libNameChanges
-
-def PerformChanges(frameworkDependencyDict, replaceFromToPairs=None, executable_path="/tmp/klayout"):
-  libNameChanges = DetectChanges(frameworkDependencyDict)
-  cmdNameId = XcodeToolChain['nameID']
-  cmdNameChg = XcodeToolChain['nameCH']
-
-  if replaceFromToPairs is not None:
-    for libNameChange in libNameChanges:
-      libNameChangeIterator = iter(libNameChange)
-      lib = next(libNameChangeIterator)
-      try:
-        dependencies = next(libNameChangeIterator)
-      except StopIteration:
-        dependencies = list()
-      for replaceFrom, replaceTo, libdir in replaceFromToPairs:
-        fileName = ResolveExecutablePath(lib.replace(replaceFrom, replaceTo), executable_path)
-        if fileName.startswith('/usr'):
-          # print(f'skipping fileName: {fileName}')
-          continue
-
-        if lib.find(replaceFrom) >= 0:
-          if libdir:
-            frameworkPath = FindFramework(lib, replaceFrom)
-          else:
-            frameworkPath = lib
-          destFrameworkPath = frameworkPath.replace(replaceFrom, replaceTo)
-          destFrameworkPath = ResolveExecutablePath(destFrameworkPath, executable_path)
-
-          if not os.path.exists(fileName):
-            print (lib.replace(replaceFrom, replaceTo), "DOES NOT EXIST")
-            print ("COPY", frameworkPath, " -> ", destFrameworkPath)
-            shutil.copytree(frameworkPath, destFrameworkPath)
-
-          nameId = lib.replace(replaceFrom, replaceTo)
-          command = "%s %s %s" % ( cmdNameId, nameId, fileName )
-          if not os.access(fileName, os.W_OK):
-            command = "chmod u+w %s; %s; chmod u-w %s" % (fileName, command, fileName)
-          # print("\t%s" % command)
-          if subprocess.call( command, shell=True ) != 0:
+    for lib in deplibs:
+        #-----------------------------------------------------------
+        # [1] Set the identification names for the library
+        #-----------------------------------------------------------
+        nameOld = "klayout.app/Contents/Frameworks/%s" % lib
+        nameNew = "@executable_path/%s/%s"  % ( relativedir, lib )
+        command = "%s %s %s" % ( cmdNameId, nameNew, nameOld )
+        if subprocess.call( command, shell=True ) != 0:
             msg = "!!! Failed to set the new identification name to <%s> !!!"
-            print( msg % fileName, file=sys.stderr )
+            print( msg % lib, file=sys.stderr )
             return 1
 
-        for dependency in dependencies:
-          if dependency.find(replaceFrom) >= 0:
-            print("\tIn:", fileName)
-            print("\tRENAME", dependency, " -> ", dependency.replace(replaceFrom, replaceTo))
+        #-----------------------------------------------------------
+        # [2] Make the application aware of the new identification
+        #-----------------------------------------------------------
+        nameOld = "%s" % lib
+        nameNew = "@executable_path/%s/%s"  % ( relativedir, lib )
+        command = "%s %s %s %s" % ( cmdNameChg, nameOld, nameNew, executable )
+        if subprocess.call( command, shell=True ) != 0:
+            msg = "!!! Failed to make the application aware of the new identification name <%s> !!!"
+            print( msg % nameNew, file=sys.stderr )
+            return 1
+    # for-lib
+    return 0
 
-            # Try changing id first
-            nameId = dependency.replace(replaceFrom, replaceTo)
-            command = "%s %s %s" % ( cmdNameId, nameId, fileName)
-            if not os.access(str(fileName), os.W_OK):
-              command = "chmod u+w %s; %s; chmod u-w %s" % (fileName, command, fileName)
-              # print("\t%s" % command)
-            if subprocess.call( command, shell=True ) != 0:
-              msg = "!!! Failed to set the new identification name to <%s> !!!"
-              print( msg % fileName, file=sys.stderr )
-              return 1
+#----------------------------------------------------------------------------------------
+## To make a library dependency dictionary by recursively walk down the lib hierarchy
+#
+# @param[in] dylibPath:     dylib path
+# @param[in] depth:         hierarchy depth (< 5)
+# @param[in] filter_regex:  filter regular expression
+#
+# @return a dictionary
+#----------------------------------------------------------------------------------------
+def WalkLibDependencyTree( dylibPath, depth=0, filter_regex=r'\t+/usr/local/opt' ):
+    otoolCm   = 'otool -L %s | grep -E "%s"' % (dylibPath, filter_regex)
+    otoolOut  = os.popen( otoolCm ).read()
+    exedepdic = DecomposeLibraryDependency( dylibPath + ":\n" + otoolOut )
+    keys      = exedepdic.keys()
+    deplibs   = exedepdic[ list(keys)[0] ]
 
-            # Rename dependencies
-            nameOld = dependency
-            nameNew = dependency.replace(replaceFrom, replaceTo)
-            command = "%s %s %s %s" % ( cmdNameChg, nameOld, nameNew, str(fileName) )
-            if not os.access(str(fileName), os.W_OK):
-              command = "chmod u+w %s; %s; chmod u-w %s" % (fileName, command, fileName)
+    if depth < 5:
+        if len(deplibs) > 0:
+            for idx, lib in enumerate(deplibs):
+                lib = str(lib)
+                if lib != list(keys)[0]:
+                    deplibs[idx] = WalkLibDependencyTree(lib, depth+1, filter_regex)
+        if depth == 0:
+            return deplibs
+        return exedepdic
+    else:
+        raise RuntimeError( "Exceeded maximum recursion depth." )
 
-            # print("\t%s" % command)
-            if subprocess.call( command, shell=True ) != 0:
-              msg = "!!! Failed to set the new identification name to <%s> !!!"
-              print( msg % fileName, file=sys.stderr )
-              return 1
+#----------------------------------------------------------------------------------------
+## To make a library dependency dictionary by recursively walk down the Framework
+#
+# @param[in] frameworkPaths:      Framework path
+# @param[in] filter_regex:        filter regular expression
+# @param[in] search_path_filter:  search path filter regular expression
+#
+# @return a dictionary
+#----------------------------------------------------------------------------------------
+def WalkFrameworkPaths( frameworkPaths, filter_regex=r'\.(so|dylib)$',
+                                                                                search_path_filter=r'\t+/usr/local/opt' ):
 
+    if isinstance(frameworkPaths, str):
+        frameworkPathsIter = [frameworkPaths]
+    else:
+        frameworkPathsIter = frameworkPaths
 
-#------------------------------------------------------------------------------
+    dependency_dict = dict()
+
+    for frameworkPath in frameworkPathsIter:
+        # print("Calling:", 'find %s -type f | grep -E "%s"' % (frameworkPath, filter_regex))
+        find_grep_results = os.popen('find %s -type f | grep -E "%s"' % (frameworkPath, filter_regex)).read().split('\n')
+        framework_files = filter(lambda x: x != '',
+                                                    map(lambda x: x.strip(),
+                                                                find_grep_results))
+
+        dependency_dict[frameworkPath] = list()
+        for idx, file in enumerate(framework_files):
+            dict_file = {file: WalkLibDependencyTree(file, filter_regex=search_path_filter)}
+            dependency_dict[frameworkPath].append(dict_file)
+    return dependency_dict
+
+#----------------------------------------------------------------------------------------
+## To make a list of changed libraries
+#
+# @param[in] dependencyDict:  library dependency dictionary
+# @param[in] visited_files:   list of visited files
+#
+# @return a list
+#----------------------------------------------------------------------------------------
+def WalkDictTree( dependencyDict, visited_files ):
+    libNameChanges = list()
+    for lib, dependencies in dependencyDict.items():
+        if lib in visited_files:
+            continue
+
+        dependency_list = list()
+        if isinstance(dependencies, list):
+            for deplib in dependencies:
+                if isinstance(deplib, str):
+                    dependency_list.append(deplib)
+                    if deplib not in visited_files:
+                        visited_files.append(deplib)
+                elif isinstance(deplib, dict):
+                    dependency_list.append(next(iter(deplib)))
+                    libNameChanges.extend(WalkDictTree(deplib, visited_files))
+                else:
+                    #raise RuntimeError("Unexpected value: %s" % deplib)
+                    pass
+        else:
+            raise RuntimeError("Unexpected value: %s" % dependencies)
+        if len(dependency_list) > 0:
+            libNameChanges.append((lib, dependency_list))
+        else:
+            libNameChanges.append((lib, ))
+        visited_files.append(lib)
+    return libNameChanges
+
+#----------------------------------------------------------------------------------------
+## To find the Framework name from a library name
+#
+# @param[in] path:      path to a library
+# @param[in] root_path: root path
+#
+# @return the path to a Framework
+#----------------------------------------------------------------------------------------
+def FindFramework( path, root_path ):
+    relPath = os.path.relpath(path, root_path)
+    frmPath = os.path.join(root_path, relPath.split(os.sep)[0])
+    #print( "###", frmPath, path, root_path )
+    return frmPath
+
+#----------------------------------------------------------------------------------------
+## To resolve an executable path
+#
+# @param[in] path:            a path to resolve
+# @param[in] executable_path: an executable path
+#
+# @return the resolved path
+#----------------------------------------------------------------------------------------
+def ResolveExecutablePath( path, executable_path ):
+    """ Transforms @executable_path into executable_path"""
+    p = path.replace("@executable_path", "/%s/" % executable_path)
+    return p
+
+#----------------------------------------------------------------------------------------
+## To detect the changed library names
+#
+# @param[in] frameworkDependencyDict: framework dependency dictionary
+#
+# @return a list of changes, each of which is stored in the form of
+#         * ('lib.dylib', ['dep1.dylib', ...])
+#           OR
+#         * ('lib.dylib',)
+#----------------------------------------------------------------------------------------
+def DetectChanges(frameworkDependencyDict):
+    visited_files = list()
+    libNameChanges = list()
+    for framework, libraries in frameworkDependencyDict.items():
+        for libraryDict in libraries:
+            libNameChanges.extend(WalkDictTree(libraryDict, visited_files))
+    return libNameChanges
+
+#----------------------------------------------------------------------------------------
+## To perform the required changes
+#
+# @param[in] frameworkDependencyDict: framework dependency dictionary
+# @param[in] replaceFromToPairs:      (from, to)-pair for replacement
+# @param[in] executable_path:         executable path
+#
+# @return 0 on success; > 0 on failure
+#----------------------------------------------------------------------------------------
+def PerformChanges( frameworkDependencyDict, replaceFromToPairs=None, executable_path="/tmp/klayout" ):
+    libNameChanges = DetectChanges(frameworkDependencyDict)
+    #print(libNameChanges)
+    cmdNameId  = XcodeToolChain['nameID']
+    cmdNameChg = XcodeToolChain['nameCH']
+
+    if replaceFromToPairs is None:
+        return 0
+    else:
+        for libNameChange in libNameChanges:
+            libNameChangeIterator = iter(libNameChange)
+            lib = next(libNameChangeIterator)
+            try:
+                dependencies = next(libNameChangeIterator)
+            except StopIteration:
+                dependencies = list()
+            for replaceFrom, replaceTo, libdir in replaceFromToPairs:
+                fileName = ResolveExecutablePath(lib.replace(replaceFrom, replaceTo), executable_path)
+                if fileName.startswith('/usr'):
+                    # print(f'skipping fileName: {fileName}')
+                    continue
+
+                if lib.find(replaceFrom) >= 0:
+                    if libdir:
+                        frameworkPath = FindFramework(lib, replaceFrom)
+                    else:
+                        frameworkPath = lib
+                    destFrameworkPath = frameworkPath.replace(replaceFrom, replaceTo)
+                    destFrameworkPath = ResolveExecutablePath(destFrameworkPath, executable_path)
+
+                    if not os.path.exists(fileName):
+                        print( "     NOT FOUND:", lib.replace(replaceFrom, replaceTo) )
+                        print( "       COPYING:", frameworkPath, " -> ", destFrameworkPath )
+                        shutil.copytree(frameworkPath, destFrameworkPath)
+
+                    nameId = lib.replace(replaceFrom, replaceTo)
+                    command = "%s %s %s" % ( cmdNameId, nameId, fileName )
+                    if not os.access(fileName, os.W_OK):
+                        command = "chmod u+w %s; %s; chmod u-w %s" % (fileName, command, fileName)
+                    # print("\t%s" % command)
+                    if subprocess.call( command, shell=True ) != 0:
+                        msg = "!!! Failed to set the new identification name to <%s> !!!"
+                        print( msg % fileName, file=sys.stderr )
+                        return 1
+
+                for dependency in dependencies:
+                    if dependency.find(replaceFrom) >= 0:
+                        print( "       IN:", fileName )
+                        print( "         RENAMING:", dependency, " -> ", dependency.replace(replaceFrom, replaceTo) )
+
+                        # Try changing id first
+                        nameId = dependency.replace(replaceFrom, replaceTo)
+                        command = "%s %s %s" % ( cmdNameId, nameId, fileName)
+                        if not os.access(str(fileName), os.W_OK):
+                            command = "chmod u+w %s; %s; chmod u-w %s" % (fileName, command, fileName)
+                            # print("\t%s" % command)
+                        if subprocess.call( command, shell=True ) != 0:
+                            msg = "!!! Failed to set the new identification name to <%s> !!!"
+                            print( msg % fileName, file=sys.stderr )
+                            return 1
+
+                        # Rename dependencies
+                        nameOld = dependency
+                        nameNew = dependency.replace(replaceFrom, replaceTo)
+                        command = "%s %s %s %s" % ( cmdNameChg, nameOld, nameNew, str(fileName) )
+                        if not os.access(str(fileName), os.W_OK):
+                            command = "chmod u+w %s; %s; chmod u-w %s" % (fileName, command, fileName)
+
+                        # print("\t%s" % command)
+                        if subprocess.call( command, shell=True ) != 0:
+                            msg = "!!! Failed to set the new identification name to <%s> !!!"
+                            print( msg % fileName, file=sys.stderr )
+                            return 1
+        return 0
+
+#----------------------------------------------------------------------------------------
 ## To get KLayout's version from a file; most likely from 'version.sh'
 #
 # @param[in] verfile   version file from which version is retrieved
 #
 # @return version string
-#------------------------------------------------------------------------------
+#----------------------------------------------------------------------------------------
 def GetKLayoutVersionFrom( verfile='version.h' ):
-  version = "?.?.?"
-  try:
-    fd = open( verfile, "r" )
-    contents = fd.readlines()
-    fd.close()
-  except Exception as e:
+    version = "?.?.?"
+    try:
+        fd = open( verfile, "r" )
+        contents = fd.readlines()
+        fd.close()
+    except Exception as e:
+        return version
+
+    verReg = re.compile( u'(KLAYOUT_VERSION=\")([0-9A-Z_a-z\.]+)(\")' )
+    for line in contents:
+        m = verReg.match(line)
+        if m:
+            # print(m.group(0)) # KLAYOUT_VERSION="0.26.1"
+            # print(m.group(1)) # KLAYOUT_VERSION="
+            # print(m.group(2)) # 0.26.1
+            # print(m.group(3)) # "
+            version = m.group(2)
+            return version
     return version
 
-  verReg = re.compile( u'(KLAYOUT_VERSION=\")([0-9A-Z_a-z\.]+)(\")' )
-  for line in contents:
-    m = verReg.match(line)
-    if m:
-      # print(m.group(0)) # KLAYOUT_VERSION="0.26.1"
-      # print(m.group(1)) # KLAYOUT_VERSION="
-      # print(m.group(2)) # 0.26.1
-      # print(m.group(3)) # "
-      version = m.group(2)
-      return version
-  return version
-
-#------------------------------------------------------------------------------
+#----------------------------------------------------------------------------------------
 ## To generate the contents of "Info.plist" file from a template
 #
 # @param[in]  keydic    dictionary of four key words ['exe', 'icon', 'bname', 'ver']
 # @param[in]  templfile template file ("macbuild/Resources/Info.plist.template")
 #
 # @return generated strings
-#------------------------------------------------------------------------------
+#----------------------------------------------------------------------------------------
 def GenerateInfoPlist( keydic, templfile ):
-  val_exe   = keydic['exe']
-  val_icon  = keydic['icon']
-  val_bname = keydic['bname']
-  val_ver   = keydic['ver']
+    val_exe   = keydic['exe']
+    val_icon  = keydic['icon']
+    val_bname = keydic['bname']
+    val_ver   = keydic['ver']
 
-  try:
-    fd = open( templfile, "r" )
-    template = fd.read()
-    fd.close()
-  except Exception as e:
-    return "???"
+    try:
+        fd = open( templfile, "r" )
+        template = fd.read()
+        fd.close()
+    except Exception as e:
+        return "???"
 
-  t = string.Template(template)
-  s = t.substitute( EXECUTABLE = val_exe,
-                    ICONFILE   = val_icon,
-                    BUNDLENAME = val_bname,
-                    VERSION    = val_ver)
-  return s
+    t = string.Template(template)
+    s = t.substitute( EXECUTABLE = val_exe,
+                                        ICONFILE   = val_icon,
+                                        BUNDLENAME = val_bname,
+                                        VERSION    = val_ver)
+    return s
 
 #----------------
 # End of File
diff --git a/macbuild/macQAT.py b/macbuild/macQAT.py
new file mode 100755
index 000000000..907330f1c
--- /dev/null
+++ b/macbuild/macQAT.py
@@ -0,0 +1,278 @@
+#!/usr/bin/env python
+# -*- coding: utf-8 -*-
+
+#===============================================================================
+# File: "macbuild/macQAT.py"
+#
+#  The top Python script to run "ut_runner" after building KLayout
+#  (http://www.klayout.de/index.php) version 0.26.1 or later on different Apple
+#  ßMac OSX platforms.
+#
+#  This script must be copied to a "*.macQAT/" directory to run.
+#===============================================================================
+from __future__ import print_function  # to use print() of Python 3 in Python >= 2.7
+import sys
+import os
+import datetime
+from   time import sleep
+import six
+import shutil
+import glob
+import platform
+import optparse
+import subprocess
+
+#-------------------------------------------------------------------------------
+## To set global variables including present directory and platform info.
+#
+#-------------------------------------------------------------------------------
+def SetGlobals():
+  global ProjectDir         # project directory where "ut_runner" exists
+  global RunnerUsage        # True to print the usage of 'ut_runner'
+  global Run                # True to run this script
+  global ContinueOnError    # True to continue after an error
+  global TestsExcluded      # list of tests to exclude
+  global Arguments          # other arguments
+  global GitSHA1            # Git's short SHA1 value of the HEAD
+  global TimeStamp          # time stamp
+  global WorkDir            # work directory name
+  global LogFile            # log file name
+  global Usage              # string on usage
+  # auxiliary variables on platform
+  global System             # 6-tuple from platform.uname()
+  global Node               # - do -
+  global Release            # - do -
+  global Version            # - do -
+  global Machine            # - do -
+  global Processor          # - do -
+  global Bit                # machine bit-size
+
+  Usage  = "\n"
+  Usage += "----------------------------------------------------------------------------------------\n"
+  Usage += "<< Usage of 'macQAT.py' >>\n"
+  Usage += "       for running 'ut_runner' after building KLayout.\n"
+  Usage += "\n"
+  Usage += "$ [python] ./macQAT.py \n"
+  Usage += "   option & argument      : descriptions                            | default value\n"
+  Usage += "   -----------------------------------------------------------------+---------------\n"
+  Usage += "   [-u|--usage]           : print usage of 'ut_runner'and exit      | disabled \n"
+  Usage += "                                                                    | \n"
+  Usage += "   <-r|--run>             : run this script                         | disabled \n"
+  Usage += "   [-s|--stop]            : stop on error                           | disabled \n"
+  Usage += "   [-x|--exclude <tests>] : exclude test(s) such as 'pymod,pya'     | '' \n"
+  Usage += "   [-a|--args <string>]   : arguments other than '-x' and '-c'      | '' \n"
+  Usage += "   [-?|--?]               : print this usage and exit               | disabled \n"
+  Usage += "--------------------------------------------------------------------+-------------------\n"
+
+  ProjectDir      = os.getcwd()
+  RunnerUsage     = False
+  Run             = False
+  ContinueOnError = True
+  TestsExcluded   = list()
+  Arguments       = ""
+  GitSHA1         = GetGitShortSHA1()
+  TimeStamp       = GetTimeStamp()
+  WorkDir         = "QATest_%s_%s__%s" % (GitSHA1, TimeStamp, os.path.basename(ProjectDir) )
+  LogFile         = WorkDir + ".log"
+
+  (System, Node, Release, Version, Machine, Processor) = platform.uname()
+
+#-------------------------------------------------------------------------------
+## Get git's short SHA1 value of the HEAD
+#
+# @return SHA1 value string
+#-------------------------------------------------------------------------------
+def GetGitShortSHA1():
+  command = "git rev-parse --short HEAD 2>/dev/null"
+  sha1val = os.popen( command ).read().strip()
+  return sha1val
+
+#-------------------------------------------------------------------------------
+## Get the time stamp
+#
+# @return time stamp string
+#-------------------------------------------------------------------------------
+def GetTimeStamp():
+  ts = datetime.datetime.today()
+  return "%04d_%02d%02d_%02d%02d" % (ts.year, ts.month, ts.day, ts.hour, ts.minute)
+
+#-------------------------------------------------------------------------------
+## To parse the command line arguments
+#
+#-------------------------------------------------------------------------------
+def ParseCommandLineArguments():
+  global Usage
+  global RunnerUsage
+  global Run
+  global ContinueOnError
+  global TestsExcluded
+  global Arguments
+
+  p = optparse.OptionParser( usage=Usage )
+  p.add_option( '-u', '--usage',
+                action='store_true',
+                dest='runner_usage',
+                default=False,
+                help="print usage of 'ut_runner' and exit (false)" )
+
+  p.add_option( '-r', '--run',
+                action='store_true',
+                dest='runme',
+                default=False,
+                help='run this script (false)' )
+
+  p.add_option( '-s', '--stop',
+                action='store_true',
+                dest='stop_on_error',
+                default=False,
+                help='stop on error (false)' )
+
+  p.add_option( '-x', '--exclude',
+                dest='exclude_tests',
+                help="exclude test(s) such as 'pymod,pya' ('')" )
+
+  p.add_option( '-a', '--args',
+                dest='arguments',
+                help="arguments other than '-x' and '-c' ('')" )
+
+  p.add_option( '-?', '--??',
+                action='store_true',
+                dest='checkusage',
+                default=False,
+                help='check usage (false)' )
+
+  p.set_defaults( runner_usage  = False,
+                  runme         = False,
+                  stop_on_error = False,
+                  exclude_tests = "",
+                  arguments     = "",
+                  checkusage    = False )
+
+  opt, args = p.parse_args()
+  if opt.checkusage:
+    print(Usage)
+    quit()
+
+  RunnerUsage     = opt.runner_usage
+  Run             = opt.runme
+  ContinueOnError = not opt.stop_on_error
+  if not opt.exclude_tests == "":
+    TestsExcluded = [ item.strip() for item in opt.exclude_tests.split(',') ]
+  else:
+    TestsExcluded = []
+  Arguments = opt.arguments
+
+#-------------------------------------------------------------------------------
+## Hide/Show the private directory
+#
+#-------------------------------------------------------------------------------
+def HidePrivateDir():
+  if os.path.isdir( "../private" ):
+    os.rename( "../private", "../private.stash"  )
+
+def ShowPrivateDir():
+  if os.path.isdir( "../private.stash" ):
+    os.rename( "../private.stash", "../private"  )
+
+#-------------------------------------------------------------------------------
+## Export environment variables for "ut_runner"
+#
+#-------------------------------------------------------------------------------
+def ExportEnvVariables():
+  global ProjectDir
+  global WorkDir
+  global MyEnviron  # my environment variables; can be independently used later
+
+  # In older versions of subprocess module, 'env=None' argument is not provided
+  MyEnviron = os.environ.copy()
+  MyEnviron[ 'TESTSRC' ] = ".."
+  MyEnviron[ 'TESTTMP' ] = WorkDir
+  if System == "Darwin":
+    MyEnviron[ 'DYLD_LIBRARY_PATH' ] = "%s:%s/db_plugins" % (ProjectDir, ProjectDir)
+    for env in [ 'TESTSRC', 'TESTTMP', 'DYLD_LIBRARY_PATH' ]:
+      os.environ[env] = MyEnviron[env]
+  else:
+    MyEnviron[ 'LD_LIBRARY_PATH' ] = "%s:%s/db_plugins" % (ProjectDir, ProjectDir)
+    for env in [ 'TESTSRC', 'TESTTMP', 'LD_LIBRARY_PATH' ]:
+      os.environ[env] = MyEnviron[env]
+
+#-------------------------------------------------------------------------------
+## Run the tester
+#
+# @param[in] command  command string to run
+# @param[in] logfile  log file name
+#-------------------------------------------------------------------------------
+def RunTester( command, logfile="" ):
+  if six.PY3:
+    proc = subprocess.Popen( command.split(), stdout=subprocess.PIPE,   \
+                                              stderr=subprocess.STDOUT, \
+                                              universal_newlines=True )
+  else:
+    proc = subprocess.Popen( command.split(), stdout=subprocess.PIPE,   \
+                                              stderr=subprocess.STDOUT )
+
+  if not logfile == "":
+    with proc.stdout, open( logfile, 'w' ) as file:
+      for line in proc.stdout:
+        sys.stdout.write(line)
+        file.write(line)
+    proc.wait()
+  else:
+    with proc.stdout:
+      for line in proc.stdout:
+        sys.stdout.write(line)
+    proc.wait()
+
+#-------------------------------------------------------------------------------
+# Main function
+#-------------------------------------------------------------------------------
+def Main():
+  #-------------------------------------------------------
+  # [1] Initialize
+  #-------------------------------------------------------
+  SetGlobals()
+  ParseCommandLineArguments()
+  ExportEnvVariables()
+
+  #-------------------------------------------------------
+  # [2] Print the runner's usage
+  #-------------------------------------------------------
+  if RunnerUsage:
+    command = './ut_runner --help-all'
+    RunTester( command )
+    quit()
+
+  #-------------------------------------------------------
+  # [3] Run the unit tester
+  #-------------------------------------------------------
+  if not Run:
+    print( "! pass <-r|--run> option to run" )
+    print(Usage)
+    quit()
+
+  command = './ut_runner'
+  if ContinueOnError:
+    command += " -c"
+  for item in TestsExcluded:
+    command += ' -x %s' % item
+  if not Arguments == "":
+    command += " %s" % Arguments
+
+  print( "" )
+  print( "### Dumping the log to <%s>" % LogFile )
+  print( "------------------------------------------------------------" )
+  print( "  Git SHA1   = %s" % GitSHA1 )
+  print( "  Time stamp = %s" % TimeStamp )
+  print( "------------------------------------------------------------" )
+  sleep( 1.0 )
+  HidePrivateDir()
+  RunTester( command, logfile=LogFile )
+  ShowPrivateDir()
+
+#===================================================================================
+if __name__ == "__main__":
+  Main()
+
+#---------------
+# End of file
+#---------------
diff --git a/macbuild/makeDMG4mac.py b/macbuild/makeDMG4mac.py
index c2429c785..5ef4edd6f 100755
--- a/macbuild/makeDMG4mac.py
+++ b/macbuild/makeDMG4mac.py
@@ -23,6 +23,7 @@ import platform
 import optparse
 import subprocess
 import hashlib
+import string
 
 #-------------------------------------------------------------------------------
 ## To import global dictionaries of different modules and utility functions
@@ -41,6 +42,7 @@ def SetGlobals():
   global GenOSName          # generic OS name
   global Platform           # platform
   global PkgDir             # the package directory where "klayout.app" exists
+  global UnsafePkg          # flags whether to proceed to making "invalid" dmg
   global OpClean            # 'clean' operation
   global OpMake             # 'make' operation
   global DefaultBundleName  # the default bundle name 'klayout.app'
@@ -87,6 +89,8 @@ def SetGlobals():
   Usage += "                        :   <-c|--clean> and <-m|--make> are mutually exclusive      | \n"
   Usage += "   [-b|--bundle <name>] : forcibly use this bundle name in the DMG                   | '' \n"
   Usage += "   [-s|--serial <num>]  : DMG serial number                                          | 1 \n"
+  Usage += "   <-u|--unsafe>        : Ignores a few checks (use with caution)                    | disabled \n"
+  Usage += "   <-t|--targetdmg>     : Specify output .dmg filename                               | chosen by script \n"
   Usage += "   [-?|--?]             : print this usage and exit                                  | disabled \n"
   Usage += "-------------------------------------------------------------------------------------+------------------\n"
 
@@ -131,6 +135,7 @@ def SetGlobals():
     sys.exit(1)
 
   PkgDir            = ""
+  UnsafePkg         = False
   OpClean           = False
   OpMake            = False
   DefaultBundleName = "klayout.app"
@@ -179,8 +184,8 @@ def SetGlobals():
 # The package directory name should look like:
 #     * ST-qt5MP.pkg.macos-Catalina-release-RsysPsys      --- (1)
 #     * LW-qt5Ana3.pkg.macos-Catalina-release-Rana3Pana3
-#     * LW-qt5Brew.pkg.macos-Catalina-release-Rhb26Phb37
-#     * LW-qt5MP.pkg.macos-Catalina-release-Rmp26Pmp37
+#     * LW-qt5Brew.pkg.macos-Catalina-release-Rhb26Phb38
+#     * LW-qt5MP.pkg.macos-Catalina-release-Rmp26Pmp38
 #
 # Generated DMG will be, for example,
 #     (1) ---> ST-klayout-0.26.1-macOS-Catalina-1-qt5MP-RsysPsys.dmg
@@ -189,6 +194,8 @@ def SetGlobals():
 #         on failure, -1
 #------------------------------------------------------------------------------
 def CheckPkgDirectory():
+  global PkgDir
+  global UnsafePkg
   global Platform
   global OpClean
   global OpMake
@@ -221,84 +228,87 @@ def CheckPkgDirectory():
   #
   #     * ST-qt5MP.pkg.macos-Catalina-release-RsysPsys
   #     * LW-qt5Ana3.pkg.macos-Catalina-release-Rana3Pana3
-  #     * LW-qt5Brew.pkg.macos-Catalina-release-Rhb27Phb37
-  #     * HW-qt5Brew.pkg.macos-Catalina-release-RsysPhb37
-  #     * EX-qt5MP.pkg.macos-Catalina-release-Rmp26Pmp37
+  #     * LW-qt5Brew.pkg.macos-Catalina-release-Rhb27Phb38
+  #     * HW-qt5Brew.pkg.macos-Catalina-release-RsysPhb38
+  #     * EX-qt5MP.pkg.macos-Catalina-release-Rmp26Pmp38
   #-----------------------------------------------------------------------------
   patQRP = u'(ST|LW|HW|EX)([-])(qt5[0-9A-Za-z]+)([.]pkg[.])([A-Za-z]+[-][A-Za-z]+[-]release[-])([0-9A-Za-z]+)'
   regQRP = re.compile(patQRP)
   if not regQRP.match(PkgDir):
     print( "! Cannot identify (Qt, Ruby, Python) from the package directory name" )
-    print( "" )
-    return -1
+    if UnsafePkg:
+      print( "! Ignoring..." )
+    else:
+      print( "" )
+      return -1
   else:
     pkgdirComponents = regQRP.match(PkgDir).groups()
     PackagePrefix    = pkgdirComponents[0]
     QtIdentification = pkgdirComponents[2]
     RubyPythonID     = pkgdirComponents[5]
 
-  #-----------------------------------------------------------------------------
-  # [3] Check if the "LatestOS" with MacPorts / Homebrew / Anaconda3
-  #-----------------------------------------------------------------------------
-  LatestOSMacPorts   = Platform == LatestOS
-  LatestOSMacPorts  &= PackagePrefix == "LW"
-  LatestOSMacPorts  &= QtIdentification == "qt5MP"
-  LatestOSMacPorts  &= RubyPythonID == "Rmp26Pmp37"
+    #-----------------------------------------------------------------------------
+    # [3] Check if the "LatestOS" with MacPorts / Homebrew / Anaconda3
+    #-----------------------------------------------------------------------------
+    LatestOSMacPorts   = Platform == LatestOS
+    LatestOSMacPorts  &= PackagePrefix == "LW"
+    LatestOSMacPorts  &= QtIdentification == "qt5MP"
+    LatestOSMacPorts  &= RubyPythonID == "Rmp26Pmp38"
 
-  LatestOSHomebrew   = Platform == LatestOS
-  LatestOSHomebrew  &= PackagePrefix == "LW"
-  LatestOSHomebrew  &= QtIdentification == "qt5Brew"
-  LatestOSHomebrew  &= RubyPythonID == "Rhb27Phb37"
+    LatestOSHomebrew   = Platform == LatestOS
+    LatestOSHomebrew  &= PackagePrefix == "LW"
+    LatestOSHomebrew  &= QtIdentification == "qt5Brew"
+    LatestOSHomebrew  &= RubyPythonID == "Rhb27Phb38"
 
-  LatestOSAnaconda3  = Platform == LatestOS
-  LatestOSAnaconda3 &= PackagePrefix == "LW"
-  LatestOSAnaconda3 &= QtIdentification == "qt5Ana3"
-  LatestOSAnaconda3 &= RubyPythonID == "Rana3Pana3"
+    LatestOSAnaconda3  = Platform == LatestOS
+    LatestOSAnaconda3 &= PackagePrefix == "LW"
+    LatestOSAnaconda3 &= QtIdentification == "qt5Ana3"
+    LatestOSAnaconda3 &= RubyPythonID == "Rana3Pana3"
 
-  if LatestOSMacPorts:
-    mydic  = DicLightWeight["ports"]
-    srcDir = PkgDir + "/" + mydic["src"]
-    desDir = PkgDir + "/" + mydic["des"]
-    if OpMake:
-      with zipfile.ZipFile( mydic["zip"], 'r' ) as zip_ref:
-        zip_ref.extractall(PkgDir)
-      os.rename( srcDir, desDir )
-    if OpClean:
-      if os.path.isdir(srcDir):
-        shutil.rmtree(srcDir)
-      if os.path.isdir(desDir):
-        shutil.rmtree(desDir)
-    Item3AppleScript = mydic["item3"]
+    if LatestOSMacPorts:
+      mydic  = DicLightWeight["ports"]
+      srcDir = PkgDir + "/" + mydic["src"]
+      desDir = PkgDir + "/" + mydic["des"]
+      if OpMake:
+        with zipfile.ZipFile( mydic["zip"], 'r' ) as zip_ref:
+          zip_ref.extractall(PkgDir)
+        os.rename( srcDir, desDir )
+      if OpClean:
+        if os.path.isdir(srcDir):
+          shutil.rmtree(srcDir)
+        if os.path.isdir(desDir):
+          shutil.rmtree(desDir)
+      Item3AppleScript = mydic["item3"]
 
-  if LatestOSHomebrew:
-    mydic  = DicLightWeight["brew"]
-    srcDir = PkgDir + "/" + mydic["src"]
-    desDir = PkgDir + "/" + mydic["des"]
-    if OpMake:
-      with zipfile.ZipFile( mydic["zip"], 'r' ) as zip_ref:
-        zip_ref.extractall(PkgDir)
-      os.rename( srcDir, desDir )
-    if OpClean:
-      if os.path.isdir(srcDir):
-        shutil.rmtree(srcDir)
-      if os.path.isdir(desDir):
-        shutil.rmtree(desDir)
-    Item3AppleScript = mydic["item3"]
+    if LatestOSHomebrew:
+      mydic  = DicLightWeight["brew"]
+      srcDir = PkgDir + "/" + mydic["src"]
+      desDir = PkgDir + "/" + mydic["des"]
+      if OpMake:
+        with zipfile.ZipFile( mydic["zip"], 'r' ) as zip_ref:
+          zip_ref.extractall(PkgDir)
+        os.rename( srcDir, desDir )
+      if OpClean:
+        if os.path.isdir(srcDir):
+          shutil.rmtree(srcDir)
+        if os.path.isdir(desDir):
+          shutil.rmtree(desDir)
+      Item3AppleScript = mydic["item3"]
 
-  if LatestOSAnaconda3:
-    mydic  = DicLightWeight["ana3"]
-    srcDir = PkgDir + "/" + mydic["src"]
-    desDir = PkgDir + "/" + mydic["des"]
-    if OpMake:
-      with zipfile.ZipFile( mydic["zip"], 'r' ) as zip_ref:
-        zip_ref.extractall(PkgDir)
-      os.rename( srcDir, desDir )
-    if OpClean:
-      if os.path.isdir(srcDir):
-        shutil.rmtree(srcDir)
-      if os.path.isdir(desDir):
-        shutil.rmtree(desDir)
-    Item3AppleScript = mydic["item3"]
+    if LatestOSAnaconda3:
+      mydic  = DicLightWeight["ana3"]
+      srcDir = PkgDir + "/" + mydic["src"]
+      desDir = PkgDir + "/" + mydic["des"]
+      if OpMake:
+        with zipfile.ZipFile( mydic["zip"], 'r' ) as zip_ref:
+          zip_ref.extractall(PkgDir)
+        os.rename( srcDir, desDir )
+      if OpClean:
+        if os.path.isdir(srcDir):
+          shutil.rmtree(srcDir)
+        if os.path.isdir(desDir):
+          shutil.rmtree(desDir)
+      Item3AppleScript = mydic["item3"]
 
   #------------------------------------------------------
   # [4] Check the presence of the default bundle
@@ -337,6 +347,7 @@ def ParseCommandLineArguments():
   global OpMake
   global BundleName
   global DMGSerialNum
+  global UnsafePkg
   global PackagePrefix
   global QtIdentification
   global RubyPythonID
@@ -369,6 +380,16 @@ def ParseCommandLineArguments():
                 dest='dmg_serial',
                 help="DMG serial number" )
 
+  p.add_option( '-t', '--targetdmg',
+                dest='target_dmg',
+                help="output DMG filename" )
+
+  p.add_option( '-z', '--unsafe',
+                action='store_true',
+                dest='unsafe',
+                default=False,
+                help="If set, do not check whether pkg folder is empty" )
+
   p.add_option( '-?', '--??',
                 action='store_true',
                 dest='checkusage',
@@ -379,7 +400,9 @@ def ParseCommandLineArguments():
                   operation_clean   = False,
                   operation_make    = False,
                   bundle_name       = "",
+                  target_dmg        = "",
                   dmg_serial        = "1",
+                  unsafe            = False,
                   checkusage        = False )
 
   #-----------------------------------------------------------
@@ -394,6 +417,7 @@ def ParseCommandLineArguments():
   OpClean      = opt.operation_clean
   OpMake       = opt.operation_make
   DMGSerialNum = int(opt.dmg_serial)
+  UnsafePkg    = opt.unsafe
 
   if not opt.bundle_name == "":
     base, ext  = os.path.splitext( os.path.basename(opt.bundle_name) )
@@ -410,10 +434,13 @@ def ParseCommandLineArguments():
   # [2] Check the PKG directory to set QtIdentification, RubyPythonID, and BundleName
   #------------------------------------------------------------------------------------
   OccupiedDS = CheckPkgDirectory()
-  if not 0 < OccupiedDS:
+  if not 0 < OccupiedDS and not UnsafePkg:
     print( "! Failed to check the PKG directory" )
     print( "" )
     quit()
+
+  if opt.target_dmg != "":
+    TargetDMG = opt.target_dmg
   else:
     TargetDMG = "%s-klayout-%s-%s-%s-%d-%s-%s.dmg" \
                 % (PackagePrefix, KLVersion, GenOSName, Platform, DMGSerialNum, QtIdentification, RubyPythonID)
@@ -663,7 +690,8 @@ def CleanUp(msg=""):
   os.chdir(ProjectDir)
   dmgs = glob.glob( "*.dmg*" )
   for item in dmgs:
-    os.system( "rm -Rf %s" % item )
+    print("Removing %s" % item)
+    os.system( "rm -Rf -- \"%s\"" % item )
 
   #----------------------------------------------------
   # [3] Clean up AppleScript if any
diff --git a/src/ant/ant/antPropertiesPage.cc b/src/ant/ant/antPropertiesPage.cc
index 0df2c3967..d98d00122 100644
--- a/src/ant/ant/antPropertiesPage.cc
+++ b/src/ant/ant/antPropertiesPage.cc
@@ -50,6 +50,38 @@ PropertiesPage::PropertiesPage (ant::Service *rulers, db::Manager *manager, QWid
   p2_to_layout->setEnabled (! readonly());
   both_to_layout->setEnabled (! readonly());
 
+  if (! readonly ()) {
+
+    connect (fmt_le, SIGNAL (editingFinished ()), this, SIGNAL (edited ()));
+    connect (fmt_x_le, SIGNAL (editingFinished ()), this, SIGNAL (edited ()));
+    connect (fmt_y_le, SIGNAL (editingFinished ()), this, SIGNAL (edited ()));
+    connect (x1, SIGNAL (editingFinished ()), this, SIGNAL (edited ()));
+    connect (x2, SIGNAL (editingFinished ()), this, SIGNAL (edited ()));
+    connect (y1, SIGNAL (editingFinished ()), this, SIGNAL (edited ()));
+    connect (y2, SIGNAL (editingFinished ()), this, SIGNAL (edited ()));
+
+    connect (style_cb, SIGNAL (activated (int)), this, SIGNAL (edited ()));
+    connect (outline_cb, SIGNAL (activated (int)), this, SIGNAL (edited ()));
+    connect (main_position, SIGNAL (activated (int)), this, SIGNAL (edited ()));
+    connect (main_xalign, SIGNAL (activated (int)), this, SIGNAL (edited ()));
+    connect (main_yalign, SIGNAL (activated (int)), this, SIGNAL (edited ()));
+    connect (xlabel_xalign, SIGNAL (activated (int)), this, SIGNAL (edited ()));
+    connect (xlabel_yalign, SIGNAL (activated (int)), this, SIGNAL (edited ()));
+    connect (ylabel_xalign, SIGNAL (activated (int)), this, SIGNAL (edited ()));
+    connect (ylabel_yalign, SIGNAL (activated (int)), this, SIGNAL (edited ()));
+
+  } else {
+
+    fmt_le->setReadOnly (true);
+    fmt_x_le->setReadOnly (true);
+    fmt_y_le->setReadOnly (true);
+    x1->setReadOnly (true);
+    x2->setReadOnly (true);
+    y1->setReadOnly (true);
+    y2->setReadOnly (true);
+
+  }
+
   lay::activate_help_links (help_label);
 
   mp_rulers->clear_highlights ();
@@ -91,7 +123,53 @@ PropertiesPage::swap_points_clicked ()
   y2->setText (ty2);
 
   db::Transaction t (manager (), tl::to_string (QObject::tr ("Swap ruler points")));
-  apply ();
+  emit edited ();
+}
+
+void
+PropertiesPage::get_points (db::DPoint &p1, db::DPoint &p2)
+{
+  double dx1 = 0.0, dy1 = 0.0, dx2 = 0.0, dy2 = 0.0;
+  bool has_error = false;
+
+  try {
+    tl::from_string (tl::to_string (x1->text ()), dx1);
+    lay::indicate_error (x1, 0);
+  } catch (tl::Exception &ex) {
+    lay::indicate_error (x1, &ex);
+    has_error = true;
+  }
+
+  try {
+    tl::from_string (tl::to_string (x2->text ()), dx2);
+    lay::indicate_error (x2, 0);
+  } catch (tl::Exception &ex) {
+    lay::indicate_error (x2, &ex);
+    has_error = true;
+  }
+
+  try {
+    tl::from_string (tl::to_string (y1->text ()), dy1);
+    lay::indicate_error (y1, 0);
+  } catch (tl::Exception &ex) {
+    lay::indicate_error (y1, &ex);
+    has_error = true;
+  }
+
+  try {
+    tl::from_string (tl::to_string (y2->text ()), dy2);
+    lay::indicate_error (y2, 0);
+  } catch (tl::Exception &ex) {
+    lay::indicate_error (y2, &ex);
+    has_error = true;
+  }
+
+  if (has_error) {
+    throw tl::Exception (tl::to_string (tr ("At least one value is invalid - see highlighted entry fields")));
+  }
+
+  p1 = db::DPoint (dx1, dy1);
+  p2 = db::DPoint (dx2, dy2);
 }
 
 void
@@ -104,13 +182,8 @@ PropertiesPage::snap_to_layout_clicked ()
   ant::Service *service = dynamic_cast<ant::Service *> (editable ());
   tl_assert (service != 0);
 
-  double dx1 = 0.0, dy1 = 0.0, dx2 = 0.0, dy2 = 0.0;
-  tl::from_string (tl::to_string (x1->text ()), dx1);
-  tl::from_string (tl::to_string (x2->text ()), dx2);
-  tl::from_string (tl::to_string (y1->text ()), dy1);
-  tl::from_string (tl::to_string (y2->text ()), dy2);
-
-  db::DPoint p1 (dx1, dy1), p2 (dx2, dy2);
+  db::DPoint p1, p2;
+  get_points (p1, p2);
 
   ant::Object r = current ();
 
@@ -137,11 +210,11 @@ PropertiesPage::snap_to_layout_clicked ()
 
     while (snap_range < max_range) {
 
-      std::pair<bool, db::DPoint> pp = lay::obj_snap (service->view (), snap_p1 ? p2 : p1, snap_p1 ? p1 : p2, g, ac, snap_range);
-      if (pp.first) {
+      lay::PointSnapToObjectResult pp = lay::obj_snap (service->view (), snap_p1 ? p2 : p1, snap_p1 ? p1 : p2, g, ac, snap_range);
+      if (pp.object_snap != lay::PointSnapToObjectResult::NoObject) {
 
-        QString xs = tl::to_qstring (tl::micron_to_string (pp.second.x ()));
-        QString ys = tl::to_qstring (tl::micron_to_string (pp.second.y ()));
+        QString xs = tl::to_qstring (tl::micron_to_string (pp.snapped_point.x ()));
+        QString ys = tl::to_qstring (tl::micron_to_string (pp.snapped_point.y ()));
 
         if (sender () == p1_to_layout) {
           x1->setText (xs);
@@ -152,7 +225,7 @@ PropertiesPage::snap_to_layout_clicked ()
         }
 
         db::Transaction t (manager (), tl::to_string (snap_p1 ? QObject::tr ("Snap first ruler point") : QObject::tr ("Snap second ruler point")));
-        apply ();
+        emit edited ();
 
         break;
 
@@ -168,16 +241,16 @@ PropertiesPage::snap_to_layout_clicked ()
     double snap_range = service->widget ()->mouse_event_trans ().inverted ().ctrans (service->snap_range ());
     snap_range *= 0.5;
 
-    std::pair<bool, db::DEdge> ee = lay::obj_snap2 (service->view (), p1, p2, g, ac, snap_range, snap_range * 1000.0);
-    if (ee.first) {
+    lay::TwoPointSnapToObjectResult ee = lay::obj_snap2 (service->view (), p1, p2, g, ac, snap_range, snap_range * 1000.0);
+    if (ee.any) {
 
-      x1->setText (tl::to_qstring (tl::micron_to_string (ee.second.p1 ().x ())));
-      y1->setText (tl::to_qstring (tl::micron_to_string (ee.second.p1 ().y ())));
-      x2->setText (tl::to_qstring (tl::micron_to_string (ee.second.p2 ().x ())));
-      y2->setText (tl::to_qstring (tl::micron_to_string (ee.second.p2 ().y ())));
+      x1->setText (tl::to_qstring (tl::micron_to_string (ee.first.x ())));
+      y1->setText (tl::to_qstring (tl::micron_to_string (ee.first.y ())));
+      x2->setText (tl::to_qstring (tl::micron_to_string (ee.second.x ())));
+      y2->setText (tl::to_qstring (tl::micron_to_string (ee.second.y ())));
 
       db::Transaction t (manager (), tl::to_string (QObject::tr ("Snap both ruler points")));
-      apply ();
+      emit edited ();
 
     }
 
@@ -268,22 +341,9 @@ PropertiesPage::readonly ()
 void 
 PropertiesPage::apply ()
 {
-  double dx1 = current ().p1 ().x (), dy1 = current ().p1 ().y ();
-  double dx2 = current ().p2 ().x (), dy2 = current ().p2 ().y ();
-
   //  only adjust the values if the text has changed
-  if (tl::to_qstring (tl::micron_to_string (dx1)) != x1->text ()) {
-    tl::from_string (tl::to_string (x1->text ()), dx1);
-  }
-  if (tl::to_qstring (tl::micron_to_string (dx2)) != x2->text ()) {
-    tl::from_string (tl::to_string (x2->text ()), dx2);
-  }
-  if (tl::to_qstring (tl::micron_to_string (dy1)) != y1->text ()) {
-    tl::from_string (tl::to_string (y1->text ()), dy1);
-  }
-  if (tl::to_qstring (tl::micron_to_string (dy2)) != y2->text ()) {
-    tl::from_string (tl::to_string (y2->text ()), dy2);
-  }
+  db::DPoint p1, p2;
+  get_points (p1, p2);
 
   std::string fmt = tl::to_string (fmt_le->text ());
   std::string fmt_x = tl::to_string (fmt_x_le->text ());
@@ -291,7 +351,7 @@ PropertiesPage::apply ()
   Object::style_type style = Object::style_type (style_cb->currentIndex ());
   Object::outline_type outline = Object::outline_type (outline_cb->currentIndex ());
 
-  ant::Object ruler (db::DPoint (dx1, dy1), db::DPoint (dx2, dy2), current ().id (), fmt_x, fmt_y, fmt, style, outline, current ().snap (), current ().angle_constraint ());
+  ant::Object ruler (p1, p2, current ().id (), fmt_x, fmt_y, fmt, style, outline, current ().snap (), current ().angle_constraint ());
 
   ruler.set_main_position (Object::position_type (main_position->currentIndex ()));
   ruler.set_main_xalign (Object::alignment_type (main_xalign->currentIndex ()));
diff --git a/src/ant/ant/antPropertiesPage.h b/src/ant/ant/antPropertiesPage.h
index 5cae57e5f..8a23b1801 100644
--- a/src/ant/ant/antPropertiesPage.h
+++ b/src/ant/ant/antPropertiesPage.h
@@ -64,6 +64,7 @@ private:
   bool m_enable_cb_callback;
 
   const ant::Object &current () const;
+  void get_points(db::DPoint &p1, db::DPoint &p2);
 };
 
 }
diff --git a/src/ant/ant/antService.cc b/src/ant/ant/antService.cc
index fd0a50dc0..62f1dcc36 100644
--- a/src/ant/ant/antService.cc
+++ b/src/ant/ant/antService.cc
@@ -706,9 +706,7 @@ View::render (const lay::Viewport &vp, lay::ViewObjectCanvas &canvas)
 //  ant::Service implementation
 
 Service::Service (db::Manager *manager, lay::LayoutView *view)
-  : lay::ViewService (view->view_object_widget ()), 
-    lay::Editable (view),
-    lay::Plugin (view),
+  : lay::EditorServiceBase (view),
     lay::Drawing (1/*number of planes*/, view->drawings ()),
     db::Object (manager),
     m_halo (true),
@@ -801,7 +799,7 @@ Service::configure (const std::string &name, const std::string &value)
     m_current_template = n;
 
   } else {
-    taken = false;
+    lay::EditorServiceBase::configure (name, value);
   }
 
   return taken;
@@ -1434,14 +1432,14 @@ Service::mouse_click_event (const db::DPoint &p, unsigned int buttons, bool prio
         double snap_range = widget ()->mouse_event_trans ().inverted ().ctrans (m_snap_range);
         snap_range *= 0.5;
 
-        std::pair<bool, db::DEdge> ee = lay::obj_snap2 (mp_view, p, g, ac, snap_range, snap_range * 1000.0);
-        if (ee.first) {
+        lay::TwoPointSnapToObjectResult ee = lay::obj_snap2 (mp_view, p, g, ac, snap_range, snap_range * 1000.0);
+        if (ee.any) {
 
           //  begin the transaction
           tl_assert (! manager ()->transacting ());
           manager ()->transaction (tl::to_string (QObject::tr ("Create ruler")));
 
-          m_current = ant::Object (ee.second.p1 (), ee.second.p2 (), 0, tpl);
+          m_current = ant::Object (ee.first, ee.second, 0, tpl);
           show_message ();
 
           insert_ruler (m_current, true);
@@ -1505,17 +1503,31 @@ Service::create_measure_ruler (const db::DPoint &pt, lay::angle_constraint_type
 
   ant::Template tpl;
 
-  std::pair<bool, db::DEdge> ee = lay::obj_snap2 (mp_view, pt, db::DVector (), ac, snap_range, snap_range * 1000.0);
-  if (ee.first) {
-    return ant::Object (ee.second.p1 (), ee.second.p2 (), 0, tpl);
+  lay::TwoPointSnapToObjectResult ee = lay::obj_snap2 (mp_view, pt, db::DVector (), ac, snap_range, snap_range * 1000.0);
+  if (ee.any) {
+    return ant::Object (ee.first, ee.second, 0, tpl);
   } else {
     return ant::Object (pt, pt, 0, tpl);
   }
 }
 
-bool 
+bool
 Service::mouse_move_event (const db::DPoint &p, unsigned int buttons, bool prio) 
 {
+  if (prio) {
+
+    lay::PointSnapToObjectResult snap_details;
+    if (m_drawing) {
+      snap_details = snap2_details (m_p1, p, mp_active_ruler->ruler (), ac_from_buttons (buttons));
+    } else {
+      const ant::Template &tpl = current_template ();
+      snap_details = snap1_details (p, m_obj_snap && tpl.snap ());
+    }
+
+    mouse_cursor_from_snap_details (snap_details);
+
+  }
+
   if (m_drawing && prio) {
 
     set_cursor (lay::Cursor::cross);
@@ -1532,12 +1544,14 @@ Service::mouse_move_event (const db::DPoint &p, unsigned int buttons, bool prio)
 void 
 Service::deactivated ()
 {
+  lay::EditorServiceBase::deactivated ();
+
   drag_cancel ();
   clear_transient_selection ();
 }
 
-std::pair<bool, db::DPoint> 
-Service::snap1 (const db::DPoint &p, bool obj_snap)
+lay::PointSnapToObjectResult
+Service::snap1_details (const db::DPoint &p, bool obj_snap)
 {
   db::DVector g;
   if (m_grid_snap) {
@@ -1548,9 +1562,16 @@ Service::snap1 (const db::DPoint &p, bool obj_snap)
   return lay::obj_snap (obj_snap ? mp_view : 0, p, g, snap_range);
 }
 
+std::pair<bool, db::DPoint>
+Service::snap1 (const db::DPoint &p, bool obj_snap)
+{
+  lay::PointSnapToObjectResult res = snap1_details (p, obj_snap);
+  return std::make_pair (res.object_snap != lay::PointSnapToObjectResult::NoObject, res.snapped_point);
+}
 
-std::pair <bool, db::DPoint>
-Service::snap2 (const db::DPoint &p1, const db::DPoint &p2, const ant::Object *obj, lay::angle_constraint_type ac)
+
+lay::PointSnapToObjectResult
+Service::snap2_details (const db::DPoint &p1, const db::DPoint &p2, const ant::Object *obj, lay::angle_constraint_type ac)
 {
   db::DVector g;
   if (m_grid_snap) {
@@ -1563,6 +1584,13 @@ Service::snap2 (const db::DPoint &p1, const db::DPoint &p2, const ant::Object *o
   return lay::obj_snap (m_obj_snap && obj->snap () ? mp_view : 0, p1, p2, g, snap_mode, snap_range);
 }
 
+std::pair <bool, db::DPoint>
+Service::snap2 (const db::DPoint &p1, const db::DPoint &p2, const ant::Object *obj, lay::angle_constraint_type ac)
+{
+  lay::PointSnapToObjectResult res = snap2_details (p1, p2, obj, ac);
+  return std::make_pair (res.object_snap != lay::PointSnapToObjectResult::NoObject, res.snapped_point);
+}
+
 
 struct RulerIdComp 
 {
diff --git a/src/ant/ant/antService.h b/src/ant/ant/antService.h
index ad7a0eaa8..0f6d3b05b 100644
--- a/src/ant/ant/antService.h
+++ b/src/ant/ant/antService.h
@@ -27,9 +27,7 @@
 
 #include "antCommon.h"
 
-#include "layViewObject.h"
-#include "layEditable.h"
-#include "layPlugin.h"
+#include "layEditorServiceBase.h"
 #include "layDrawing.h"
 #include "laySnap.h"
 #include "layAnnotationShapes.h"
@@ -180,9 +178,7 @@ private:
 // -------------------------------------------------------------
 
 class ANT_PUBLIC Service
-  : public lay::ViewService,
-    public lay::Editable,
-    public lay::Plugin,
+  : public lay::EditorServiceBase,
     public lay::Drawing,
     public db::Object
 {
@@ -529,8 +525,10 @@ private:
   unsigned int m_current_template;
 
   std::pair<bool, db::DPoint> snap1 (const db::DPoint &p, bool obj_snap);
+  lay::PointSnapToObjectResult snap1_details (const db::DPoint &p, bool obj_snap);
   std::pair<bool, db::DPoint> snap2 (const db::DPoint &p1, const db::DPoint &p2, const ant::Object *obj, lay::angle_constraint_type ac);
-  
+  lay::PointSnapToObjectResult snap2_details (const db::DPoint &p1, const db::DPoint &p2, const ant::Object *obj, lay::angle_constraint_type ac);
+
   const ant::Template &current_template () const;
 
   void show_message ();
diff --git a/src/db/db/db.pro b/src/db/db/db.pro
index a911e1a03..763633f3e 100644
--- a/src/db/db/db.pro
+++ b/src/db/db/db.pro
@@ -190,6 +190,7 @@ SOURCES = \
     gsiDeclDbNetlistCrossReference.cc \
     gsiDeclDbLayoutVsSchematic.cc \
     dbNetlistObject.cc \
+    dbD25TechnologyComponent.cc \
     gsiDeclDbTexts.cc \
     dbTexts.cc \
     dbDeepTexts.cc \
@@ -354,6 +355,7 @@ HEADERS = \
     dbLayoutVsSchematicFormatDefs.h \
     dbLayoutVsSchematic.h \
     dbNetlistObject.h \
+    dbD25TechnologyComponent.h \
     dbTexts.h \
     dbDeepTexts.h \
     dbAsIfFlatTexts.h \
diff --git a/src/db/db/dbCell.cc b/src/db/db/dbCell.cc
index 0b1522e82..4a1adf813 100644
--- a/src/db/db/dbCell.cc
+++ b/src/db/db/dbCell.cc
@@ -506,7 +506,7 @@ Cell::collect_caller_cells (std::set<cell_index_type> &callers, const std::set<c
 {
   if (levels != 0) {
     for (parent_cell_iterator cc = begin_parent_cells (); cc != end_parent_cells (); ++cc) {
-      if (cone.find (*cc) != cone.end () && callers.find (*cc) == callers.end ()) { 
+      if (cone.find (*cc) != cone.end () && callers.find (*cc) == callers.end () && mp_layout->is_valid_cell_index (*cc)) {
         callers.insert (*cc);
         mp_layout->cell (*cc).collect_caller_cells (callers, levels < 0 ? levels : levels - 1);
       }
@@ -519,7 +519,7 @@ Cell::collect_caller_cells (std::set<cell_index_type> &callers, int levels) cons
 {
   if (levels != 0) {
     for (parent_cell_iterator cc = begin_parent_cells (); cc != end_parent_cells (); ++cc) {
-      if (callers.find (*cc) == callers.end ()) { 
+      if (callers.find (*cc) == callers.end () && mp_layout->is_valid_cell_index (*cc)) {
         callers.insert (*cc);
         mp_layout->cell (*cc).collect_caller_cells (callers, levels < 0 ? levels : levels - 1);
       }
@@ -538,7 +538,7 @@ Cell::collect_called_cells (std::set<cell_index_type> &called, int levels) const
 {
   if (levels != 0) {
     for (child_cell_iterator cc = begin_child_cells (); ! cc.at_end (); ++cc) {
-      if (called.find (*cc) == called.end ()) { 
+      if (called.find (*cc) == called.end () && mp_layout->is_valid_cell_index (*cc)) {
         called.insert (*cc);
         mp_layout->cell (*cc).collect_called_cells (called, levels < 0 ? levels : levels - 1);
       }
diff --git a/src/db/db/dbCommonReader.cc b/src/db/db/dbCommonReader.cc
index 9802aedb9..2d4afc86d 100644
--- a/src/db/db/dbCommonReader.cc
+++ b/src/db/db/dbCommonReader.cc
@@ -29,6 +29,361 @@
 namespace db
 {
 
+// ---------------------------------------------------------------
+//  Common reader implementation
+
+static const size_t null_id = std::numeric_limits<size_t>::max ();
+
+CommonReader::CommonReader ()
+  : m_cc_resolution (AddToCell)
+{
+  //  .. nothing yet ..
+}
+
+db::cell_index_type
+CommonReader::make_cell (db::Layout &layout, const std::string &cn)
+{
+  tl_assert (! cn.empty ());
+
+  std::map<std::string, std::pair<size_t, db::cell_index_type> >::iterator iname = m_name_map.find (cn);
+  if (iname != m_name_map.end ()) {
+
+    db::Cell &cell = layout.cell (iname->second.second);
+
+    if (! cell.is_ghost_cell ()) {
+      common_reader_error (tl::sprintf (tl::to_string (tr ("A cell with name %s already exists")), cn));
+    }
+
+    cell.set_ghost_cell (false);
+    return cell.cell_index ();
+
+  } else {
+
+    db::cell_index_type ci = layout.add_anonymous_cell ();
+
+    m_name_map [cn] = std::make_pair (null_id, ci);
+    return ci;
+
+  }
+}
+
+bool
+CommonReader::has_cell (const std::string &cn) const
+{
+  return m_name_map.find (cn) != m_name_map.end ();
+}
+
+std::pair<bool, db::cell_index_type>
+CommonReader::cell_by_name (const std::string &cn) const
+{
+  std::map<std::string, std::pair<size_t, db::cell_index_type> >::const_iterator iname = m_name_map.find (cn);
+  if (iname != m_name_map.end ()) {
+    return std::make_pair (true, iname->second.second);
+  } else {
+    return std::make_pair (false, size_t (0));
+  }
+}
+
+db::cell_index_type
+CommonReader::make_cell (db::Layout &layout, size_t id)
+{
+  tl_assert (id != null_id);
+
+  std::map<size_t, std::pair<std::string, db::cell_index_type> >::iterator iid = m_id_map.find (id);
+  if (iid != m_id_map.end ()) {
+
+    db::Cell &cell = layout.cell (iid->second.second);
+
+    if (! cell.is_ghost_cell ()) {
+      common_reader_error (tl::sprintf (tl::to_string (tr ("A cell with ID %ld already exists")), id));
+    }
+
+    cell.set_ghost_cell (false);
+    return cell.cell_index ();
+
+  } else {
+
+    db::cell_index_type ci = layout.add_anonymous_cell ();
+
+    m_id_map [id] = std::make_pair (std::string (), ci);
+    return ci;
+
+  }
+}
+
+bool
+CommonReader::has_cell (size_t id) const
+{
+  return m_id_map.find (id) != m_id_map.end ();
+}
+
+std::pair<bool, db::cell_index_type>
+CommonReader::cell_by_id (size_t id) const
+{
+  std::map<size_t, std::pair<std::string, db::cell_index_type> >::const_iterator iid = m_id_map.find (id);
+  if (iid != m_id_map.end ()) {
+    return std::make_pair (true, iid->second.second);
+  } else {
+    return std::make_pair (false, size_t (0));
+  }
+}
+
+const std::string &
+CommonReader::name_for_id (size_t id) const
+{
+  std::map<size_t, std::string>::const_iterator n = m_name_for_id.find (id);
+  if (n != m_name_for_id.end ()) {
+    return n->second;
+  } else {
+    static std::string empty;
+    return empty;
+  }
+}
+
+void
+CommonReader::rename_cell (db::Layout &layout, size_t id, const std::string &cn)
+{
+  m_name_for_id.insert (std::make_pair (id, cn));
+
+  std::map<size_t, std::pair<std::string, db::cell_index_type> >::iterator iid = m_id_map.find (id);
+  std::map<std::string, std::pair<size_t, db::cell_index_type> >::iterator iname = m_name_map.find (cn);
+
+  if (iid != m_id_map.end () && iname != m_name_map.end ()) {
+
+    if (! iid->second.first.empty () && iid->second.first != cn) {
+      common_reader_error (tl::sprintf (tl::to_string (tr ("Cell named %s with ID %ld was already given name %s")), cn, id, iid->second.first));
+    }
+
+    if (iname->second.second != iid->second.second) {
+
+      //  Both cells already exist and are not identical: merge ID-declared cell into the name-declared one
+      layout.force_update ();
+      merge_cell (layout, iname->second.second, iid->second.second);
+      iid->second.second = iname->second.second;
+
+    }
+
+    iid->second.first = cn;
+    iname->second.first = id;
+
+  } else if (iid != m_id_map.end ()) {
+
+    m_name_map [cn] = std::make_pair (id, iid->second.second);
+    iid->second.first = cn;
+
+  } else if (iname != m_name_map.end ()) {
+
+    m_id_map [id] = std::make_pair (cn, iname->second.second);
+    iname->second.first = id;
+
+  } else {
+
+    db::cell_index_type ci = layout.add_anonymous_cell ();
+    layout.cell (ci).set_ghost_cell (true);
+
+    m_id_map [id] = std::make_pair (cn, ci);
+    m_name_map [cn] = std::make_pair (id, ci);
+
+  }
+}
+
+db::cell_index_type
+CommonReader::cell_for_instance (db::Layout &layout, size_t id)
+{
+  tl_assert (id != null_id);
+
+  std::map<size_t, std::pair<std::string, db::cell_index_type> >::iterator iid = m_id_map.find (id);
+  if (iid != m_id_map.end ()) {
+
+    return iid->second.second;
+
+  } else {
+
+    db::cell_index_type ci = layout.add_anonymous_cell ();
+    layout.cell (ci).set_ghost_cell (true);
+
+    m_id_map [id] = std::make_pair (std::string (), ci);
+    return ci;
+
+  }
+}
+
+db::cell_index_type
+CommonReader::cell_for_instance (db::Layout &layout, const std::string &cn)
+{
+  tl_assert (! cn.empty ());
+
+  std::map<std::string, std::pair<size_t, db::cell_index_type> >::iterator iname = m_name_map.find (cn);
+  if (iname != m_name_map.end ()) {
+
+    return iname->second.second;
+
+  } else {
+
+    db::cell_index_type ci = layout.add_anonymous_cell ();
+    layout.cell (ci).set_ghost_cell (true);
+
+    m_name_map [cn] = std::make_pair (null_id, ci);
+    return ci;
+
+  }
+}
+
+void
+CommonReader::merge_cell (db::Layout &layout, db::cell_index_type target_cell_index, db::cell_index_type src_cell_index) const
+{
+  const db::Cell &src_cell = layout.cell (src_cell_index);
+  db::Cell &target_cell = layout.cell (target_cell_index);
+
+  //  copy over the instances
+  for (db::Cell::const_iterator i = src_cell.begin (); ! i.at_end (); ++i) {
+    //  NOTE: cell indexed may be invalid because we delete subcells without update()
+    if (layout.is_valid_cell_index (i->cell_index ())) {
+      target_cell.insert (*i);
+    }
+  }
+
+  merge_cell_without_instances (layout, target_cell_index, src_cell_index);
+}
+
+void
+CommonReader::merge_cell_without_instances (db::Layout &layout, db::cell_index_type target_cell_index, db::cell_index_type src_cell_index) const
+{
+  const db::Cell &src_cell = layout.cell (src_cell_index);
+  db::Cell &target_cell = layout.cell (target_cell_index);
+
+  //  copy over the shapes
+  for (unsigned int l = 0; l < layout.layers (); ++l) {
+    if (layout.is_valid_layer (l) && ! src_cell.shapes (l).empty ()) {
+      target_cell.shapes (l).insert (src_cell.shapes (l));
+    }
+  }
+
+  //  replace all instances of the new cell with the original one
+  std::vector<std::pair<db::cell_index_type, db::Instance> > parents;
+  for (db::Cell::parent_inst_iterator pi = src_cell.begin_parent_insts (); ! pi.at_end (); ++pi) {
+    parents.push_back (std::make_pair (pi->parent_cell_index (), pi->child_inst ()));
+  }
+
+  for (std::vector<std::pair<db::cell_index_type, db::Instance> >::const_iterator p = parents.begin (); p != parents.end (); ++p) {
+    db::CellInstArray ia = p->second.cell_inst ();
+    ia.object ().cell_index (target_cell.cell_index ());
+    layout.cell (p->first).replace (p->second, ia);
+  }
+
+  //  finally delete the new cell
+  layout.delete_cell (src_cell.cell_index ());
+}
+
+void
+CommonReader::finish (db::Layout &layout)
+{
+  bool any_missing = false;
+
+  for (std::map<size_t, std::pair<std::string, db::cell_index_type> >::const_iterator i = m_id_map.begin (); i != m_id_map.end (); ++i) {
+    if (i->second.first.empty ()) {
+      common_reader_warn (tl::sprintf (tl::to_string (tr ("No cellname defined for cell name id %ld")), i->first));
+      any_missing = true;
+    }
+  }
+
+  if (any_missing) {
+    common_reader_error (tl::to_string (tr ("Some cell IDs don't have a name (see previous warnings)")));
+  }
+
+  //  check if we need to resolve conflicts
+
+  bool has_conflict = false;
+  for (std::map<std::string, std::pair<size_t, db::cell_index_type> >::const_iterator i = m_name_map.begin (); i != m_name_map.end () && ! has_conflict; ++i) {
+    has_conflict = layout.cell_by_name (i->first.c_str ()).first;
+  }
+
+  if (! has_conflict) {
+
+    //  no conflict - plain rename
+
+    for (std::map<std::string, std::pair<size_t, db::cell_index_type> >::const_iterator i = m_name_map.begin (); i != m_name_map.end () && ! has_conflict; ++i) {
+      layout.rename_cell (i->second.second, i->first.c_str ());
+    }
+
+  } else {
+
+    //  elaborate conflict resolution
+
+    layout.force_update ();
+
+    std::map<db::cell_index_type, std::string> new_cells;
+    for (std::map<std::string, std::pair<size_t, db::cell_index_type> >::const_iterator i = m_name_map.begin (); i != m_name_map.end (); ++i) {
+      new_cells.insert (std::make_pair (i->second.second, i->first));
+    }
+
+    std::vector<std::pair<db::cell_index_type, db::cell_index_type> > cells_with_conflict;
+
+    //  First treat all the cells without conflict
+    for (db::Layout::bottom_up_iterator bu = layout.begin_bottom_up (); bu != layout.end_bottom_up (); ++bu) {
+
+      db::cell_index_type ci_new = *bu;
+      std::map<db::cell_index_type, std::string>::const_iterator i = new_cells.find (ci_new);
+
+      if (i == new_cells.end ()) {
+        //  not a new cell
+        continue;
+      }
+
+      std::pair<bool, db::cell_index_type> c2n = layout.cell_by_name (i->second.c_str ());
+      db::cell_index_type ci_org = c2n.second;
+
+      //  NOTE: proxy cells are never resolved. "RenameCell" is a plain and simple case.
+      if (c2n.first && m_cc_resolution != RenameCell && ! layout.cell (ci_org).is_proxy ()) {
+        cells_with_conflict.push_back (std::make_pair (ci_new, ci_org));
+      } else {
+        layout.rename_cell (ci_new, layout.uniquify_cell_name (i->second.c_str ()).c_str ());
+      }
+
+    }
+
+    //  Then treat all the cells with conflict
+    for (std::vector<std::pair<db::cell_index_type, db::cell_index_type> >::const_iterator cc = cells_with_conflict.begin (); cc != cells_with_conflict.end (); ++cc) {
+
+      db::cell_index_type ci_new = cc->first;
+      db::cell_index_type ci_org = cc->second;
+
+      //  we have a cell conflict
+
+      if (m_cc_resolution == OverwriteCell && ! layout.cell (ci_new).is_ghost_cell ()) {
+
+        if (! layout.cell (ci_org).begin ().at_end ()) {
+
+          //  NOTE: because prune_subcells needs the parents for sub cells and we are going do delete
+          //  the current cell, we cannot save the "update()" just by traversing bottom-up.
+          layout.force_update ();
+          layout.prune_subcells (ci_org);
+
+        }
+
+        layout.cell (ci_org).clear_shapes ();
+
+        merge_cell (layout, ci_org, ci_new);
+
+      } else if (m_cc_resolution == SkipNewCell && ! layout.cell (ci_org).is_ghost_cell ()) {
+
+        layout.prune_subcells (ci_new);
+        layout.cell (ci_new).clear_shapes ();
+
+        //  NOTE: ignore instances -> this saves us a layout update
+        merge_cell_without_instances (layout, ci_org, ci_new);
+
+      } else {
+
+        merge_cell (layout, ci_org, ci_new);
+
+      }
+
+    }
+
+  }
+}
+
 // ---------------------------------------------------------------
 //  Common format declaration
 
diff --git a/src/db/db/dbCommonReader.h b/src/db/db/dbCommonReader.h
index 45c09861d..f0ed56bcf 100644
--- a/src/db/db/dbCommonReader.h
+++ b/src/db/db/dbCommonReader.h
@@ -31,6 +31,128 @@
 namespace db
 {
 
+/**
+ *  @brief A common reader base for GDS2 and OASIS providing common services for both readers
+ */
+class DB_PUBLIC CommonReader
+  : public ReaderBase
+{
+public:
+  /**
+   *  @brief The CellConflictResolution enum
+   */
+  enum CellConflictResolution
+  {
+    AddToCell = 0,
+    OverwriteCell = 1,
+    SkipNewCell = 2,
+    RenameCell = 3
+  };
+
+  /**
+   *  @brief Constructor
+   */
+  CommonReader ();
+
+  /**
+   *  @brief Sets the cell name conflict resolution mode
+   */
+  void set_cell_conflict_resolution (CellConflictResolution cc_resolution)
+  {
+    m_cc_resolution = cc_resolution;
+  }
+
+  /**
+   *  @brief Sets the cell name conflict resolution mode
+   */
+  CellConflictResolution cell_conflict_resolution () const
+  {
+    return m_cc_resolution;
+  }
+
+  /**
+   *  @brief Make a cell from a name
+   */
+  db::cell_index_type make_cell (db::Layout &layout, const std::string &cn);
+
+  /**
+   *  @brief Returns true, if there is a cell with the given name already
+   */
+  bool has_cell (const std::string &cn) const;
+
+  /**
+   *  @brief Returns a pair with a bool (indicating whether the cell name is known) and the cell index for this name
+   */
+  std::pair<bool, db::cell_index_type> cell_by_name (const std::string &name) const;
+
+  /**
+   *  @brief Make a cell from an ID (OASIS)
+   */
+  db::cell_index_type make_cell (db::Layout &layout, size_t id);
+
+  /**
+   *  @brief Returns true, if there is a cell with the given ID alreay
+   */
+  bool has_cell (size_t id) const;
+
+  /**
+   *  @brief Returns a pair with a bool (indicating whether the cell ID is known) and the cell index for this ID
+   */
+  std::pair<bool, db::cell_index_type> cell_by_id (size_t id) const;
+
+  /**
+   *  @brief Registers a cell name for an ID
+   */
+  void rename_cell (db::Layout &layout, size_t id, const std::string &cn);
+
+  /**
+   *  @brief Gets the name for a given cell ID if known, otherwise returns an empty string
+   */
+  const std::string &name_for_id (size_t id) const;
+
+  /**
+   *  @brief Returns a cell reference by ID
+   *  If the cell does not exist, it's created. It is marked as ghost cell until
+   *  "make_cell" is called.
+   */
+  db::cell_index_type cell_for_instance (db::Layout &layout, size_t id);
+
+  /**
+   *  @brief Returns a cell reference by name
+   *  Same as the previous method, but acting on cell names.
+   */
+  db::cell_index_type cell_for_instance (db::Layout &layout, const std::string &cn);
+
+  /**
+   *  @brief Finishes the reading process
+   *
+   *  This method will first check if all cells IDs got a name.
+   *  After this, the cells are renamed and cell conflict resolution will happen in the
+   *  specified way (cell_conflict_resolution attribute).
+   */
+  void finish (db::Layout &layout);
+
+protected:
+  virtual void common_reader_error (const std::string &msg) = 0;
+  virtual void common_reader_warn (const std::string &msg) = 0;
+
+  /**
+   * @brief Merge (and delete) the src_cell into target_cell
+   */
+  void merge_cell (db::Layout &layout, db::cell_index_type target_cell_index, db::cell_index_type src_cell_index) const;
+
+  /**
+   * @brief Merge (and delete) the src_cell into target_cell without instances
+   */
+  void merge_cell_without_instances (db::Layout &layout, db::cell_index_type target_cell_index, db::cell_index_type src_cell_index) const;
+
+private:
+  std::map<size_t, std::pair<std::string, db::cell_index_type> > m_id_map;
+  std::map<std::string, std::pair<size_t, db::cell_index_type> > m_name_map;
+  std::map<size_t, std::string> m_name_for_id;
+  CellConflictResolution m_cc_resolution;
+};
+
 /**
  *  @brief Structure that holds the GDS2 and OASIS specific options for the reader
  */
@@ -44,7 +166,8 @@ public:
   CommonReaderOptions ()
     : create_other_layers (true),
       enable_text_objects (true),
-      enable_properties (true)
+      enable_properties (true),
+      cell_conflict_resolution (CommonReader::AddToCell)
   {
     //  .. nothing yet ..
   }
@@ -83,6 +206,22 @@ public:
    */
   bool enable_properties;
 
+  /**
+   *  @brief Specifies the cell merge behavior
+   *
+   *  This enum controls how cells are read if a cell with the requested name already
+   *  exists.
+   *
+   *  AddToCell       In this mode, instances or shapes are added to any existing cell
+   *  OverwriteCell   Overwrite existing cell. If the existing cell has children, those are removed unless used otherwise
+   *  SkipNewCell     Ignore the new cell and it's children
+   *  RenameCell      Rename the new cell
+   *
+   *  If the existing opr the new cell is a ghost cell, AddToCell is applied always. In other words,
+   *  ghost cells are always merged.
+   */
+  CommonReader::CellConflictResolution cell_conflict_resolution;
+
   /** 
    *  @brief Implementation of FormatSpecificReaderOptions
    */
diff --git a/src/db/db/dbD25TechnologyComponent.cc b/src/db/db/dbD25TechnologyComponent.cc
new file mode 100644
index 000000000..1ab0ed2ea
--- /dev/null
+++ b/src/db/db/dbD25TechnologyComponent.cc
@@ -0,0 +1,332 @@
+
+/*
+
+  KLayout Layout Viewer
+  Copyright (C) 2006-2020 Matthias Koefferlein
+
+  This program is free software; you can redistribute it and/or modify
+  it under the terms of the GNU General Public License as published by
+  the Free Software Foundation; either version 2 of the License, or
+  (at your option) any later version.
+
+  This program is distributed in the hope that it will be useful,
+  but WITHOUT ANY WARRANTY; without even the implied warranty of
+  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+  GNU General Public License for more details.
+
+  You should have received a copy of the GNU General Public License
+  along with this program; if not, write to the Free Software
+  Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
+
+*/
+
+#include "dbD25TechnologyComponent.h"
+#include "tlClassRegistry.h"
+#include "tlString.h"
+
+namespace db
+{
+
+std::string d25_component_name ()
+{
+  return std::string ("d25");
+}
+
+std::string d25_description ()
+{
+  return tl::to_string (tr ("Z stack (2.5d)"));
+}
+
+// -----------------------------------------------------------------------------------------
+//  D25LayerInfo implementation
+
+D25LayerInfo::D25LayerInfo ()
+  : m_layer (), m_zstart (0.0), m_zstop (0.0)
+{
+  //  .. nothing yet ..
+}
+
+D25LayerInfo::~D25LayerInfo ()
+{
+  //  .. nothing yet ..
+}
+
+D25LayerInfo::D25LayerInfo (const D25LayerInfo &other)
+{
+  operator= (other);
+}
+
+D25LayerInfo &
+D25LayerInfo::operator= (const D25LayerInfo &other)
+{
+  if (this != &other) {
+    m_layer = other.m_layer;
+    m_zstart = other.m_zstart;
+    m_zstop = other.m_zstop;
+  }
+  return *this;
+}
+
+bool
+D25LayerInfo::operator== (const D25LayerInfo &other) const
+{
+  return fabs (m_zstart - other.m_zstart) < db::epsilon && fabs (m_zstop - other.m_zstop) < db::epsilon;
+}
+
+void
+D25LayerInfo::set_layer (const db::LayerProperties &l)
+{
+  m_layer = l;
+}
+
+void
+D25LayerInfo::set_layer_from_string (const std::string &l)
+{
+  db::LayerProperties lp;
+  tl::Extractor ex (l.c_str ());
+  try {
+    lp.read (ex);
+  } catch (tl::Exception &) {
+    //  ignore errors for now.
+  }
+  m_layer = lp;
+}
+
+std::string
+D25LayerInfo::layer_as_string () const
+{
+  return m_layer.to_string ();
+}
+
+void
+D25LayerInfo::set_zstart (double z0)
+{
+  m_zstart = z0;
+}
+
+void
+D25LayerInfo::set_zstop (double z1)
+{
+  m_zstop = z1;
+}
+
+// -----------------------------------------------------------------------------------
+//  D25TechnologyComponent implementation
+
+D25TechnologyComponent::D25TechnologyComponent ()
+  : db::TechnologyComponent (d25_component_name (), d25_description ())
+{
+  //  provide some explanation for the initialization
+  m_src =
+    "# Provide z stack information here\n"
+    "# Each line is one layer. The specification consists of a layer specification, a colon and arguments.\n"
+    "# The arguments are named (like \"x=...\") or in serial. Parameters are separated by comma or blanks.\n"
+    "# Named arguments are:\n"
+    "#\n"
+    "#   zstart   The lower z position of the extruded layer in µm\n"
+    "#   zstop    The upper z position of the extruded layer in µm\n"
+    "#   height   The height of the extruded layer in µm\n"
+    "#\n"
+    "# 'height', 'zstart' and 'zstop' can be used in any combination. If no value is given for 'zstart', "
+    "# the upper level of the previous layer will be used.\n"
+    "#\n"
+    "# If a single unnamed parameter is given, it corresponds to 'height'. Two parameters correspond to\n"
+    "# 'zstart' and 'zstop'.\n"
+    "#\n"
+    "# Examples:\n"
+    "#   1: 0.5 1.5                    # extrude layer 1/0 from 0.5 to 1.5 vertically\n"
+    "#   1/0: 0.5 1.5                  # same with explicit datatype\n"
+    "#   1: zstop=1.5, zstart=0.5      # same with named parameters\n"
+    "#   1: height=1.0, zstop=1.5      # same with z stop minus height\n"
+    "#   1: 1.0 zstop=1.5              # same with height as unnamed parameter\n"
+  ;
+}
+
+D25TechnologyComponent::D25TechnologyComponent (const D25TechnologyComponent &d)
+  : db::TechnologyComponent (d25_component_name (), d25_description ())
+{
+  m_layers = d.m_layers;
+  m_src = d.m_src;
+}
+
+void
+D25TechnologyComponent::compile_from_source (const std::string &src)
+{
+  int current_line = 0;
+  m_layers.clear ();
+
+  try {
+
+    std::vector<std::string> lines = tl::split (src, "\n");
+    for (std::vector<std::string>::const_iterator l = lines.begin (); l != lines.end (); ++l) {
+
+      ++current_line;
+
+      tl::Extractor ex (l->c_str ());
+
+      if (ex.test ("#")) {
+        //  ignore comments
+      } else if (ex.at_end ()) {
+        //  ignore empty lines
+      } else {
+
+        db::D25LayerInfo info;
+        if (! m_layers.empty ()) {
+          info.set_zstart (m_layers.back ().zstop ());
+          info.set_zstop (m_layers.back ().zstop ());
+        }
+
+        tl::Variant z0, z1, h;
+        std::vector<double> args;
+
+        db::LayerProperties lp;
+        lp.read (ex);
+        info.set_layer (lp);
+
+        ex.expect (":");
+
+        while (! ex.at_end ()) {
+
+          if (ex.test ("#")) {
+            break;
+          }
+
+          double pv = 0.0;
+
+          std::string pn;
+          if (ex.try_read_name (pn)) {
+            ex.expect ("=");
+            ex.read (pv);
+          } else {
+            ex.read (pv);
+          }
+
+          ex.test (",");
+
+          if (pn.empty ()) {
+            args.push_back (pv);
+          } else if (pn == "zstart") {
+            z0 = pv;
+          } else if (pn == "zstop") {
+            z1 = pv;
+          } else if (pn == "height") {
+            h = pv;
+          } else {
+            throw tl::Exception (tl::to_string (tr ("Invalid parameter name: ")) + pn);
+          }
+
+        }
+
+        if (args.size () == 0) {
+          if (z0.is_nil () && z1.is_nil ()) {
+            if (! h.is_nil ()) {
+              info.set_zstop (info.zstart () + h.to_double ());
+            }
+          } else if (z0.is_nil ()) {
+            info.set_zstop (z1.to_double ());
+            if (! h.is_nil ()) {
+              info.set_zstart (info.zstop () - h.to_double ());
+            }
+          } else if (z1.is_nil ()) {
+            info.set_zstart (z0.to_double ());
+            if (! h.is_nil ()) {
+              info.set_zstop (info.zstart () + h.to_double ());
+            }
+          } else {
+            info.set_zstart (z0.to_double ());
+            info.set_zstop (z1.to_double ());
+          }
+        } else if (args.size () == 1) {
+          if (! h.is_nil ()) {
+            if (! z0.is_nil ()) {
+              throw tl::Exception (tl::to_string (tr ("Rundundant parameters: zstart already given")));
+            }
+            if (! z1.is_nil ()) {
+              throw tl::Exception (tl::to_string (tr ("Rundundant parameters: zstop implicitly given")));
+            }
+            info.set_zstart (args[0]);
+            info.set_zstop (args[0] + h.to_double ());
+          } else {
+            if (! z1.is_nil ()) {
+              throw tl::Exception (tl::to_string (tr ("Rundundant parameters: zstop implicitly given")));
+            }
+            info.set_zstop ((! z0.is_nil () ? z0.to_double () : info.zstart ()) + args[0]);
+          }
+        } else if (args.size () == 2) {
+          if (! z0.is_nil ()) {
+            throw tl::Exception (tl::to_string (tr ("Rundundant parameters: zstart already given")));
+          }
+          if (! z1.is_nil ()) {
+            throw tl::Exception (tl::to_string (tr ("Rundundant parameters: zstop already given")));
+          }
+          if (! h.is_nil ()) {
+            throw tl::Exception (tl::to_string (tr ("Rundundant parameters: height implicitly given")));
+          }
+          info.set_zstart (args[0]);
+          info.set_zstop (args[1]);
+        } else {
+          throw tl::Exception (tl::to_string (tr ("Too many parameters (max 2)")));
+        }
+
+        m_layers.push_back (info);
+
+      }
+
+    }
+
+  } catch (tl::Exception &ex) {
+    throw tl::Exception (ex.msg () + tl::sprintf (tl::to_string (tr (" in line %d")), current_line));
+  }
+
+  m_src = src;
+}
+
+std::string
+D25TechnologyComponent::to_string () const
+{
+  std::string res;
+
+  for (const_iterator i = begin (); i != end (); ++i) {
+    if (! res.empty ()) {
+      res += "\n";
+    }
+    res += i->layer ().to_string () + ": zstart=" + tl::to_string (i->zstart ()) + ", zstop=" + tl::to_string (i->zstop ());
+  }
+
+  return res;
+}
+
+// -----------------------------------------------------------------------------------
+//  D25TechnologyComponent technology component registration
+
+class D25TechnologyComponentProvider
+  : public db::TechnologyComponentProvider
+{
+public:
+  D25TechnologyComponentProvider ()
+    : db::TechnologyComponentProvider ()
+  {
+    //  .. nothing yet ..
+  }
+
+  virtual db::TechnologyComponent *create_component () const
+  {
+    return new D25TechnologyComponent ();
+  }
+
+  virtual tl::XMLElementBase *xml_element () const
+  {
+    return new db::TechnologyComponentXMLElement<D25TechnologyComponent> (d25_component_name (),
+      tl::make_element ((D25TechnologyComponent::const_iterator (D25TechnologyComponent::*) () const) &D25TechnologyComponent::begin, (D25TechnologyComponent::const_iterator (D25TechnologyComponent::*) () const) &D25TechnologyComponent::end, &D25TechnologyComponent::add, "layer",
+        tl::make_member (&D25LayerInfo::layer_as_string, &D25LayerInfo::set_layer_from_string, "layer") +
+        tl::make_member (&D25LayerInfo::zstart, &D25LayerInfo::set_zstart, "zstart") +
+        tl::make_member (&D25LayerInfo::zstop, &D25LayerInfo::set_zstop, "zstop")
+      ) +
+      tl::make_member (&D25TechnologyComponent::src, &D25TechnologyComponent::set_src, "src")
+    );
+  }
+};
+
+static tl::RegisteredClass<db::TechnologyComponentProvider> tc_decl (new D25TechnologyComponentProvider (), 3100, d25_component_name ().c_str ());
+
+}
diff --git a/src/db/db/dbD25TechnologyComponent.h b/src/db/db/dbD25TechnologyComponent.h
new file mode 100644
index 000000000..4c31363c1
--- /dev/null
+++ b/src/db/db/dbD25TechnologyComponent.h
@@ -0,0 +1,154 @@
+
+/*
+
+  KLayout Layout Viewer
+  Copyright (C) 2006-2020 Matthias Koefferlein
+
+  This program is free software; you can redistribute it and/or modify
+  it under the terms of the GNU General Public License as published by
+  the Free Software Foundation; either version 2 of the License, or
+  (at your option) any later version.
+
+  This program is distributed in the hope that it will be useful,
+  but WITHOUT ANY WARRANTY; without even the implied warranty of
+  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+  GNU General Public License for more details.
+
+  You should have received a copy of the GNU General Public License
+  along with this program; if not, write to the Free Software
+  Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
+
+*/
+
+#ifndef HDR_dbD25TechnologyComponent
+#define HDR_dbD25TechnologyComponent
+
+#include "dbTechnology.h"
+#include "dbLayerProperties.h"
+
+namespace db
+{
+
+class DB_PUBLIC D25LayerInfo
+{
+public:
+  D25LayerInfo ();
+  ~D25LayerInfo ();
+  D25LayerInfo (const D25LayerInfo &other);
+  D25LayerInfo &operator= (const D25LayerInfo &other);
+
+  bool operator== (const D25LayerInfo &other) const;
+
+  const db::LayerProperties &layer () const
+  {
+    return m_layer;
+  }
+
+  void set_layer_from_string (const std::string &l);
+  std::string layer_as_string () const;
+
+  void set_layer (const db::LayerProperties &l);
+
+  double zstart () const
+  {
+    return m_zstart;
+  }
+
+  void set_zstart (double z0);
+
+  double zstop () const
+  {
+    return m_zstop;
+  }
+
+  void set_zstop (double z1);
+
+private:
+  db::LayerProperties m_layer;
+  double m_zstart, m_zstop;
+};
+
+class DB_PUBLIC D25TechnologyComponent
+  : public db::TechnologyComponent
+{
+public:
+  D25TechnologyComponent ();
+  D25TechnologyComponent (const D25TechnologyComponent &d);
+
+  typedef std::list<D25LayerInfo> layers_type;
+  typedef layers_type::const_iterator const_iterator;
+  typedef layers_type::iterator iterator;
+
+  void compile_from_source (const std::string &src);
+
+  const_iterator begin () const
+  {
+    return m_layers.begin ();
+  }
+
+  iterator begin ()
+  {
+    return m_layers.begin ();
+  }
+
+  const_iterator end () const
+  {
+    return m_layers.end ();
+  }
+
+  iterator end ()
+  {
+    return m_layers.end ();
+  }
+
+  void clear ()
+  {
+    m_layers.clear ();
+  }
+
+  void erase (iterator p)
+  {
+    m_layers.erase (p);
+  }
+
+  void insert (iterator p, const D25LayerInfo &info)
+  {
+    m_layers.insert (p, info);
+  }
+
+  void add (const D25LayerInfo &info)
+  {
+    m_layers.push_back (info);
+  }
+
+  size_t size () const
+  {
+    return m_layers.size ();
+  }
+
+  const std::string &src () const
+  {
+    return m_src;
+  }
+
+  //  for persistency only, use "compile_from_source" to read from a source string
+  void set_src (const std::string &s)
+  {
+    m_src = s;
+  }
+
+  std::string to_string () const;
+
+  db::TechnologyComponent *clone () const
+  {
+    return new D25TechnologyComponent (*this);
+  }
+
+private:
+  layers_type m_layers;
+  std::string m_src;
+};
+
+}
+
+#endif
diff --git a/src/db/db/dbDeepShapeStore.cc b/src/db/db/dbDeepShapeStore.cc
index f95667da2..42f72e17d 100644
--- a/src/db/db/dbDeepShapeStore.cc
+++ b/src/db/db/dbDeepShapeStore.cc
@@ -931,7 +931,7 @@ DeepShapeStore::cell_mapping_to_original (unsigned int layout_index, db::Layout
     cm = m_delivery_mapping_cache.insert (std::make_pair (key, db::CellMapping ())).first;
 
     //  collects the cell mappings we skip because they are variants (variant building or box variants)
-    std::map<db::cell_index_type, std::pair<db::cell_index_type, std::set<db::Box> > > cm_skipped_variants;
+    std::map<db::cell_index_type, db::HierarchyBuilder::CellMapKey> cm_skipped_variants;
 
     if (into_layout == original_builder.source ().layout () && &into_layout->cell (into_cell) == original_builder.source ().top_cell ()) {
 
@@ -945,14 +945,14 @@ DeepShapeStore::cell_mapping_to_original (unsigned int layout_index, db::Layout
         HierarchyBuilder::cell_map_type::const_iterator mm = m;
         ++mm;
         bool skip = original_builder.is_variant (m->second);   //  skip variant cells
-        while (mm != original_builder.end_cell_map () && mm->first.first == m->first.first) {
+        while (mm != original_builder.end_cell_map () && mm->first.original_cell == m->first.original_cell) {
           //  we have cell (box) variants and cannot simply map
           ++mm;
           skip = true;
         }
 
         if (! skip) {
-          cm->second.map (m->second, m->first.first);
+          cm->second.map (m->second, m->first.original_cell);
         } else {
           for (HierarchyBuilder::cell_map_type::const_iterator n = m; n != mm; ++n) {
             tl_assert (cm_skipped_variants.find (n->second) == cm_skipped_variants.end ());
@@ -988,17 +988,19 @@ DeepShapeStore::cell_mapping_to_original (unsigned int layout_index, db::Layout
 
       db::cell_index_type var_org = original_builder.original_target_for_variant (np->first);
 
-      std::map<db::cell_index_type, std::pair<db::cell_index_type, std::set<db::Box> > >::const_iterator icm = cm_skipped_variants.find (var_org);
+      std::map<db::cell_index_type, db::HierarchyBuilder::CellMapKey>::const_iterator icm = cm_skipped_variants.find (var_org);
       if (icm != cm_skipped_variants.end ()) {
 
         //  create the variant clone in the original layout too and delete this cell
-        VariantsCollectorBase::copy_shapes (*into_layout, np->second, icm->second.first);
-        cells_to_delete.insert (icm->second.first);
+        VariantsCollectorBase::copy_shapes (*into_layout, np->second, icm->second.original_cell);
+        cells_to_delete.insert (icm->second.original_cell);
 
         //  forget the original cell (now separated into variants) and map the variants back into the
         //  DSS layout
         original_builder.unmap (icm->second);
-        original_builder.map (std::make_pair (np->second, icm->second.second), np->first);
+        db::HierarchyBuilder::CellMapKey k = icm->second;
+        k.original_cell = np->second;
+        original_builder.map (k, np->first);
 
         //  forget the variant as now it's a real cell in the source layout
         original_builder.unregister_variant (np->first);
diff --git a/src/db/db/dbHierNetworkProcessor.cc b/src/db/db/dbHierNetworkProcessor.cc
index 46a6c406f..0992120f7 100644
--- a/src/db/db/dbHierNetworkProcessor.cc
+++ b/src/db/db/dbHierNetworkProcessor.cc
@@ -799,10 +799,18 @@ struct cluster_building_receiver
   typedef std::set<size_t> global_nets;
   typedef std::pair<shape_vector, global_nets> cluster_value;
 
-  cluster_building_receiver (const db::Connectivity &conn)
-    : mp_conn (&conn)
+  cluster_building_receiver (const db::Connectivity &conn, const tl::equivalence_clusters<size_t> *attr_equivalence)
+    : mp_conn (&conn), mp_attr_equivalence (attr_equivalence)
   {
-    //  .. nothing yet..
+    if (mp_attr_equivalence) {
+      //  cache the global nets per attribute equivalence cluster
+      for (size_t gid = 0; gid < conn.global_nets (); ++gid) {
+        tl::equivalence_clusters<size_t>::cluster_id_type cl = attr_equivalence->cluster_id (global_net_id_to_attr (gid));
+        if (cl > 0) {
+          m_global_nets_by_attribute_cluster [cl].insert (gid);
+        }
+      }
+    }
   }
 
   void generate_clusters (local_clusters<T> &clusters)
@@ -817,7 +825,32 @@ struct cluster_building_receiver
         cluster->add_attr (s->second.second);
       }
 
-      cluster->set_global_nets (c->second);
+      std::set<size_t> global_nets = c->second;
+
+      //  Add the global nets we derive from the attribute equivalence (join_nets of labelled vs.
+      //  global nets)
+      if (mp_attr_equivalence) {
+
+        for (typename shape_vector::const_iterator s = c->first.begin (); s != c->first.end (); ++s) {
+
+          size_t a = s->second.second;
+          if (a == 0) {
+            continue;
+          }
+
+          tl::equivalence_clusters<size_t>::cluster_id_type cl = mp_attr_equivalence->cluster_id (a);
+          if (cl > 0) {
+            std::map<size_t, std::set<size_t> >::const_iterator gn = m_global_nets_by_attribute_cluster.find (cl);
+            if (gn != m_global_nets_by_attribute_cluster.end ()) {
+              global_nets.insert (gn->second.begin (), gn->second.end ());
+            }
+          }
+
+        }
+
+      }
+
+      cluster->set_global_nets (global_nets);
 
     }
   }
@@ -913,6 +946,8 @@ private:
   std::map<const T *, typename std::list<cluster_value>::iterator> m_shape_to_clusters;
   std::map<size_t, typename std::list<cluster_value>::iterator> m_global_to_clusters;
   std::list<cluster_value> m_clusters;
+  std::map<size_t, std::set<size_t> > m_global_nets_by_attribute_cluster;
+  const tl::equivalence_clusters<size_t> *mp_attr_equivalence;
 
   void join (typename std::list<cluster_value>::iterator ic1, typename std::list<cluster_value>::iterator ic2)
   {
@@ -1035,7 +1070,7 @@ local_clusters<T>::build_clusters (const db::Cell &cell, const db::Connectivity
     }
   }
 
-  cluster_building_receiver<T, box_type> rec (conn);
+  cluster_building_receiver<T, box_type> rec (conn, attr_equivalence);
   bs.process (rec, 1 /*==touching*/, bc);
   rec.generate_clusters (*this);
 
@@ -1048,36 +1083,27 @@ template <class T>
 void
 local_clusters<T>::apply_attr_equivalences (const tl::equivalence_clusters<size_t> &attr_equivalence)
 {
-  tl::equivalence_clusters<size_t> eq;
-
-  //  collect all local attributes (the ones which are present in attr_equivalence) into "eq"
-  //  and form equivalences for multi-attribute clusters.
-  for (const_iterator c = begin (); c != end (); ++c) {
-    typename local_cluster<T>::attr_iterator a0;
-    for (typename local_cluster<T>::attr_iterator a = c->begin_attr (); a != c->end_attr (); ++a) {
-      if (attr_equivalence.has_attribute (*a)) {
-        if (a0 == typename local_cluster<T>::attr_iterator ()) {
-          a0 = a;
-        }
-        eq.same (*a0, *a);
-      }
-    }
-  }
-
-  //  apply the equivalences implied by attr_equivalence
-  eq.apply_equivalences (attr_equivalence);
-
   //  identify the layout clusters joined into one attribute cluster and join them
 
   std::map<tl::equivalence_clusters<size_t>::cluster_id_type, std::set<size_t> > c2c;
 
   for (const_iterator c = begin (); c != end (); ++c) {
+
     for (typename local_cluster<T>::attr_iterator a = c->begin_attr (); a != c->end_attr (); ++a) {
       tl::equivalence_clusters<size_t>::cluster_id_type cl = attr_equivalence.cluster_id (*a);
       if (cl > 0) {
         c2c [cl].insert (c->id ());
       }
     }
+
+    for (typename local_cluster<T>::global_nets_iterator g = c->begin_global_nets (); g != c->end_global_nets (); ++g) {
+      size_t a = global_net_id_to_attr (*g);
+      tl::equivalence_clusters<size_t>::cluster_id_type cl = attr_equivalence.cluster_id (a);
+      if (cl > 0) {
+        c2c [cl].insert (c->id ());
+      }
+    }
+
   }
 
   for (std::map<tl::equivalence_clusters<size_t>::cluster_id_type, std::set<size_t> >::const_iterator c = c2c.begin (); c != c2c.end (); ++c) {
diff --git a/src/db/db/dbHierNetworkProcessor.h b/src/db/db/dbHierNetworkProcessor.h
index be84db6da..1161ea84a 100644
--- a/src/db/db/dbHierNetworkProcessor.h
+++ b/src/db/db/dbHierNetworkProcessor.h
@@ -1396,11 +1396,11 @@ private:
 
 /**
  *  @brief A helper function generating an attribute ID from a property ID
- *  This function is used to provide a generic attribute wrapping a property ID and a text ID.
+ *  This function is used to provide a generic attribute wrapping a property ID, text ID and global net ID
  */
 inline size_t prop_id_to_attr (db::properties_id_type id)
 {
-  return size_t (id) * 2;
+  return size_t (id) * 4;
 }
 
 /**
@@ -1408,7 +1408,7 @@ inline size_t prop_id_to_attr (db::properties_id_type id)
  */
 inline bool is_prop_id_attr (size_t attr)
 {
-  return (attr & 1) == 0;
+  return (attr & 3) == 0;
 }
 
 /**
@@ -1416,7 +1416,32 @@ inline bool is_prop_id_attr (size_t attr)
  */
 inline db::properties_id_type prop_id_from_attr (size_t attr)
 {
-  return attr / 2;
+  return attr / 4;
+}
+
+/**
+ *  @brief A helper function generating an attribute ID from a global net ID
+ *  This function is used to provide a generic attribute wrapping a property ID, text ID and global net ID
+ */
+inline size_t global_net_id_to_attr (size_t id)
+{
+  return size_t (id) * 4 + 2;
+}
+
+/**
+ *  @brief Gets a value indicating whether the attribute is a global net ID
+ */
+inline bool is_global_net_id_attr (size_t attr)
+{
+  return (attr & 3) == 2;
+}
+
+/**
+ *  @brief Gets the global net ID from an attribute
+ */
+inline size_t global_net_id_from_attr (size_t attr)
+{
+  return attr / 4;
 }
 
 /**
@@ -1424,9 +1449,18 @@ inline db::properties_id_type prop_id_from_attr (size_t attr)
  */
 inline size_t text_ref_to_attr (const db::Text *tr)
 {
+  //  NOTE: pointers are 32bit aligned, hence the lower two bits are 0
   return size_t (tr) + 1;
 }
 
+/**
+ *  @brief Gets a value indicating whether the attribute is a StringRef
+ */
+inline bool is_text_ref_attr (size_t attr)
+{
+  return (attr & 3) == 1;
+}
+
 /**
  *  @brief Gets the text value from an attribute ID
  */
diff --git a/src/db/db/dbHierarchyBuilder.cc b/src/db/db/dbHierarchyBuilder.cc
index 968052d54..0d02600ca 100644
--- a/src/db/db/dbHierarchyBuilder.cc
+++ b/src/db/db/dbHierarchyBuilder.cc
@@ -62,6 +62,14 @@ compare_iterators_with_respect_to_target_hierarchy (const db::RecursiveShapeIter
     return iter1.max_depth () < iter2.max_depth () ? -1 : 1;
   }
 
+  //  take potential selection of cells into account
+  if (iter1.disables () != iter2.disables ()) {
+    return iter1.disables () < iter2.disables () ? -1 : 1;
+  }
+  if (iter1.enables () != iter2.enables ()) {
+    return iter1.enables () < iter2.enables () ? -1 : 1;
+  }
+
   //  if a region is set, the hierarchical appearance is the same only if the layers and
   //  complex region are identical
   if ((iter1.region () == db::Box::world ()) != (iter2.region () == db::Box::world ())) {
@@ -238,11 +246,11 @@ HierarchyBuilder::begin (const RecursiveShapeIterator *iter)
     return;
   }
 
-  std::pair<db::cell_index_type, std::set<db::Box> > key (iter->top_cell ()->cell_index (), std::set<db::Box> ());
+  CellMapKey key (iter->top_cell ()->cell_index (), false, std::set<db::Box> ());
   m_cm_entry = m_cell_map.find (key);
 
   if (m_cm_entry == m_cell_map.end ()) {
-    db::cell_index_type new_top_index = mp_target->add_cell (iter->layout ()->cell_name (key.first));
+    db::cell_index_type new_top_index = mp_target->add_cell (iter->layout ()->cell_name (key.original_cell));
     m_cm_entry = m_cell_map.insert (std::make_pair (key, new_top_index)).first;
   }
 
@@ -300,27 +308,47 @@ HierarchyBuilder::leave_cell (const RecursiveShapeIterator * /*iter*/, const db:
   m_cell_stack.pop_back ();
 }
 
+db::cell_index_type
+HierarchyBuilder::make_cell_variant (const HierarchyBuilder::CellMapKey &key, const std::string &cell_name)
+{
+  m_cm_entry = m_cell_map.find (key);
+  m_cm_new_entry = false;
+
+  db::cell_index_type new_cell;
+
+  if (m_cm_entry == m_cell_map.end ()) {
+
+    std::string cn = cell_name;
+    if (! key.clip_region.empty ()) {
+      cn += "$CLIP_VAR";
+    }
+    if (key.inactive) {
+      cn += "$DIS";
+    }
+    new_cell = mp_target->add_cell (cn.c_str ());
+    m_cm_entry = m_cell_map.insert (std::make_pair (key, new_cell)).first;
+    m_cm_new_entry = true;
+    m_cells_to_be_filled.insert (new_cell);
+
+  } else {
+    new_cell = m_cm_entry->second;
+  }
+
+  return new_cell;
+}
+
 HierarchyBuilder::new_inst_mode
 HierarchyBuilder::new_inst (const RecursiveShapeIterator *iter, const db::CellInstArray &inst, const db::Box & /*region*/, const box_tree_type * /*complex_region*/, bool all)
 {
   if (all) {
 
-    std::pair<db::cell_index_type, std::set<db::Box> > key (inst.object ().cell_index (), std::set<db::Box> ());
-
-    m_cm_entry = m_cell_map.find (key);
-    m_cm_new_entry = false;
-
-    if (m_cm_entry == m_cell_map.end ()) {
-      db::cell_index_type new_cell = mp_target->add_cell (iter->layout ()->cell_name (inst.object ().cell_index ()));
-      m_cm_entry = m_cell_map.insert (std::make_pair (key, new_cell)).first;
-      m_cm_new_entry = true;
-      m_cells_to_be_filled.insert (new_cell);
-    }
+    CellMapKey key (inst.object ().cell_index (), iter->is_child_inactive (inst.object ().cell_index ()), std::set<db::Box> ());
+    db::cell_index_type new_cell = make_cell_variant (key, iter->layout ()->cell_name (inst.object ().cell_index ()));
 
     //  for new cells, create this instance
     if (m_cell_stack.back ().first) {
       db::CellInstArray new_inst (inst, &mp_target->array_repository ());
-      new_inst.object () = db::CellInst (m_cm_entry->second);
+      new_inst.object () = db::CellInst (new_cell);
       new_inst.transform_into (m_trans);
       for (std::vector<db::Cell *>::const_iterator c = m_cell_stack.back ().second.begin (); c != m_cell_stack.back ().second.end (); ++c) {
         (*c)->insert (new_inst);
@@ -353,24 +381,12 @@ HierarchyBuilder::new_inst_member (const RecursiveShapeIterator *iter, const db:
       return false;
     }
 
-    std::pair<db::cell_index_type, std::set<db::Box> > key (inst.object ().cell_index (), clip_variant.second);
-    m_cm_entry = m_cell_map.find (key);
-    m_cm_new_entry = false;
-
-    if (m_cm_entry == m_cell_map.end ()) {
-      std::string suffix;
-      if (! key.second.empty ()) {
-        suffix = "$CLIP_VAR";
-      }
-      db::cell_index_type new_cell = mp_target->add_cell ((std::string (iter->layout ()->cell_name (inst.object ().cell_index ())) + suffix).c_str ());
-      m_cm_entry = m_cell_map.insert (std::make_pair (key, new_cell)).first;
-      m_cm_new_entry = true;
-      m_cells_to_be_filled.insert (new_cell);
-    }
+    CellMapKey key (inst.object ().cell_index (), iter->is_child_inactive (inst.object ().cell_index ()), clip_variant.second);
+    db::cell_index_type new_cell = make_cell_variant (key, iter->layout ()->cell_name (inst.object ().cell_index ()));
 
     //  for a new cell, create this instance
     if (m_cell_stack.back ().first) {
-      db::CellInstArray new_inst (db::CellInst (m_cm_entry->second), trans);
+      db::CellInstArray new_inst (db::CellInst (new_cell), trans);
       new_inst.transform_into (m_trans);
       for (std::vector<db::Cell *>::const_iterator c = m_cell_stack.back ().second.begin (); c != m_cell_stack.back ().second.end (); ++c) {
         (*c)->insert (new_inst);
diff --git a/src/db/db/dbHierarchyBuilder.h b/src/db/db/dbHierarchyBuilder.h
index 2ddd6fe22..970f2e2a5 100644
--- a/src/db/db/dbHierarchyBuilder.h
+++ b/src/db/db/dbHierarchyBuilder.h
@@ -225,8 +225,36 @@ class DB_PUBLIC HierarchyBuilder
   : public db::RecursiveShapeReceiver
 {
 public:
+  struct CellMapKey
+  {
+    CellMapKey ()
+      : original_cell (0), inactive (false)
+    { }
 
-  typedef std::map<std::pair<db::cell_index_type, std::set<db::Box> >, db::cell_index_type> cell_map_type;
+    CellMapKey (db::cell_index_type _original_cell, bool _inactive, const std::set<db::Box> &_clip_region)
+      : original_cell (_original_cell), inactive (_inactive), clip_region (_clip_region)
+    { }
+
+    bool operator== (const CellMapKey &other) const
+    {
+      return original_cell == other.original_cell && inactive == other.inactive && clip_region == other.clip_region;
+    }
+
+    bool operator< (const CellMapKey &other) const
+    {
+      if (original_cell != other.original_cell) { return original_cell < other.original_cell; }
+      if (inactive != other.inactive) { return inactive < other.inactive; }
+      if (clip_region != other.clip_region) { return clip_region < other.clip_region; }
+      return false;
+    }
+
+    db::cell_index_type original_cell;
+    bool inactive;
+    std::set<db::Box> clip_region;
+  };
+
+
+  typedef std::map<CellMapKey, db::cell_index_type> cell_map_type;
   typedef std::map<db::cell_index_type, std::vector<db::cell_index_type> > original_target_to_variants_map_type;
   typedef std::map<db::cell_index_type, db::cell_index_type> variant_to_original_target_map_type;
 
@@ -346,6 +374,8 @@ public:
   db::cell_index_type original_target_for_variant (db::cell_index_type ci) const;
 
 private:
+  db::cell_index_type make_cell_variant (const HierarchyBuilder::CellMapKey &key, const std::string &cell_name);
+
   tl::weak_ptr<db::Layout> mp_target;
   HierarchyBuilderShapeReceiver *mp_pipe;
   bool m_initial_pass;
diff --git a/src/db/db/dbLayout.cc b/src/db/db/dbLayout.cc
index 55c19ef78..199441231 100644
--- a/src/db/db/dbLayout.cc
+++ b/src/db/db/dbLayout.cc
@@ -1068,14 +1068,41 @@ Layout::add_cell (const char *name)
   return new_index;
 }
 
+cell_index_type
+Layout::add_anonymous_cell ()
+{
+  std::string b;
+
+  //  create a new cell
+  cell_index_type new_index = allocate_new_cell ();
+
+  cell_type *new_cell = new cell_type (new_index, *this);
+  m_cells.push_back_ptr (new_cell);
+  m_cell_ptrs [new_index] = new_cell;
+
+  //  enter it's index and cell_name
+  register_cell_name (0, new_index);
+
+  if (manager () && manager ()->transacting ()) {
+    manager ()->queue (this, new NewRemoveCellOp (new_index, m_cell_names [new_index], false /*new*/, 0));
+  }
+
+  return new_index;
+}
+
 void 
 Layout::register_cell_name (const char *name, cell_index_type ci)
 {
   //  enter it's index and cell_name
   char *cp;
 
-  cp = new char [strlen (name) + 1];
-  strcpy (cp, name);
+  if (name == 0) {
+    cp = new char [1];
+    *cp = 0;
+  } else {
+    cp = new char [strlen (name) + 1];
+    strcpy (cp, name);
+  }
 
   while (m_cell_names.size () < ci) {
     char *e = new char [1];
@@ -1090,7 +1117,9 @@ Layout::register_cell_name (const char *name, cell_index_type ci)
     m_cell_names.push_back (cp);
   }
 
-  m_cell_map.insert (std::make_pair (cp, ci));
+  if (name) {
+    m_cell_map.insert (std::make_pair (cp, ci));
+  }
 }
 
 void
diff --git a/src/db/db/dbLayout.h b/src/db/db/dbLayout.h
index 827dee2b3..fd6d897aa 100644
--- a/src/db/db/dbLayout.h
+++ b/src/db/db/dbLayout.h
@@ -727,7 +727,17 @@ public:
    */
   cell_index_type add_cell (const char *name = 0);
 
-  /** 
+  /**
+   *  @brief Add a cell without a name
+   *
+   *  The cell is created, but cannot be found by name. The name returned is an empty string.
+   *  The cell is created with the purpose of being renamed later.
+   *
+   *  @return The index of the new cell
+   */
+  cell_index_type add_anonymous_cell ();
+
+  /**
    *  @brief Rename a cell
    *
    *  Rename the cell with the given id.
@@ -1065,8 +1075,7 @@ public:
    *  @brief Delete the subcells of the given cells which are not used otherwise
    *
    *  All subcells referenced directy or indirectly but not used otherwise
-   *  are deleted as well. This basically prunes the cell tree by this cell.
-   *  All instances of this cell are deleted as well.
+   *  are deleted as well.
    *  This method is more efficent than calling prune_subcells for single cells multiple times.
    *
    *  @param from A begin iterator delivering the cell id's to delete
@@ -1085,8 +1094,7 @@ public:
    *  @brief Delete the subcells of the given cells which are not used otherwise
    *
    *  All subcells referenced directy or indirectly but not used otherwise
-   *  are deleted as well. This basically prunes the cell tree by this cell.
-   *  All instances of this cell are deleted as well.
+   *  are deleted as well.
    *  This method is more efficent than calling prune_subcells for single cells multiple times.
    *
    *  @param cells A set of cell id's to prune
diff --git a/src/db/db/dbNetlistExtractor.cc b/src/db/db/dbNetlistExtractor.cc
index 7783ffbc6..0067f9517 100644
--- a/src/db/db/dbNetlistExtractor.cc
+++ b/src/db/db/dbNetlistExtractor.cc
@@ -51,7 +51,7 @@ void NetlistExtractor::set_include_floating_subcircuits (bool f)
 }
 
 static void
-build_net_name_equivalence (const db::Layout *layout, db::property_names_id_type net_name_id, const std::string &joined_net_names, tl::equivalence_clusters<size_t> &eq)
+build_net_name_equivalence (const db::Layout *layout, const db::Connectivity &conn, db::property_names_id_type net_name_id, const std::string &joined_net_names, tl::equivalence_clusters<size_t> &eq)
 {
   std::map<std::string, std::set<size_t> > prop_by_name;
   tl::GlobPattern jn_pattern (joined_net_names);
@@ -67,6 +67,14 @@ build_net_name_equivalence (const db::Layout *layout, db::property_names_id_type
     }
   }
 
+  //  include pseudo-attributes for global nets to implement "join_with" for global nets
+  for (size_t gid = 0; gid < conn.global_nets (); ++gid) {
+    const std::string &gn = conn.global_net_name (gid);
+    if (jn_pattern.match (gn)) {
+      prop_by_name [gn].insert (db::global_net_id_to_attr (gid));
+    }
+  }
+
   const db::repository<db::Text> &text_repository = layout->shape_repository ().repository (db::object_tag<db::Text> ());
   for (db::repository<db::Text>::iterator t = text_repository.begin (); t != text_repository.end (); ++t) {
     std::string nn = t->string ();
@@ -107,12 +115,12 @@ NetlistExtractor::extract_nets (const db::DeepShapeStore &dss, unsigned int layo
   std::map<db::cell_index_type, tl::equivalence_clusters<size_t> > net_name_equivalence;
   if (m_text_annot_name_id.first) {
     if (! m_joined_net_names.empty ()) {
-      build_net_name_equivalence (mp_layout, m_text_annot_name_id.second, m_joined_net_names, net_name_equivalence [hier_clusters_type::top_cell_index]);
+      build_net_name_equivalence (mp_layout, conn, m_text_annot_name_id.second, m_joined_net_names, net_name_equivalence [hier_clusters_type::top_cell_index]);
     }
     for (std::list<std::pair<std::string, std::string> >::const_iterator m = m_joined_net_names_per_cell.begin (); m != m_joined_net_names_per_cell.end (); ++m) {
       std::pair<bool, db::cell_index_type> cp = mp_layout->cell_by_name (m->first.c_str ());
       if (cp.first) {
-        build_net_name_equivalence (mp_layout, m_text_annot_name_id.second, m->second, net_name_equivalence [cp.second]);
+        build_net_name_equivalence (mp_layout, conn, m_text_annot_name_id.second, m->second, net_name_equivalence [cp.second]);
       }
     }
   }
@@ -313,7 +321,7 @@ void NetlistExtractor::collect_labels (const connected_clusters_type &clusters,
 
       }
 
-    } else {
+    } else if (db::is_text_ref_attr (*a)) {
 
       net_names.insert (db::text_from_attr (*a));
 
diff --git a/src/db/db/dbNetlistSpiceReader.cc b/src/db/db/dbNetlistSpiceReader.cc
index 129fc248d..c019ef7c4 100644
--- a/src/db/db/dbNetlistSpiceReader.cc
+++ b/src/db/db/dbNetlistSpiceReader.cc
@@ -104,46 +104,66 @@ bool NetlistSpiceReaderDelegate::element (db::Circuit *circuit, const std::strin
   std::string cn = model;
   db::DeviceClass *cls = circuit->netlist ()->device_class_by_name (cn);
 
-  if (cls) {
+  if (element == "R") {
 
-    //  use given class
-
-  } else if (element == "R") {
-
-    if (cn.empty ()) {
-      cn = "RES";
+    if (cls) {
+      if (! dynamic_cast<db::DeviceClassResistor *>(cls)) {
+        error (tl::sprintf (tl::to_string (tr ("Class %s not a resistor device class as required by 'R' element")), cn));
+      }
+    } else {
+      if (cn.empty ()) {
+        cn = "RES";
+      }
+      cls = make_device_class<db::DeviceClassResistor> (circuit, cn);
     }
-    cls = make_device_class<db::DeviceClassResistor> (circuit, cn);
 
     //  Apply multiplier
     value /= mult;
 
   } else if (element == "L") {
 
-    if (cn.empty ()) {
-      cn = "IND";
+    if (cls) {
+      if (! dynamic_cast<db::DeviceClassInductor *>(cls)) {
+        error (tl::sprintf (tl::to_string (tr ("Class %s not a inductor device class as required by 'L' element")), cn));
+      }
+    } else {
+      if (cn.empty ()) {
+        cn = "IND";
+      }
+      cls = make_device_class<db::DeviceClassInductor> (circuit, cn);
     }
-    cls = make_device_class<db::DeviceClassInductor> (circuit, cn);
 
     //  Apply multiplier
     value /= mult;
 
   } else if (element == "C") {
 
-    if (cn.empty ()) {
-      cn = "CAP";
+    if (cls) {
+      if (! dynamic_cast<db::DeviceClassCapacitor *>(cls)) {
+        error (tl::sprintf (tl::to_string (tr ("Class %s not a capacitor device class as required by 'C' element")), cn));
+      }
+    } else {
+      if (cn.empty ()) {
+        cn = "CAP";
+      }
+      cls = make_device_class<db::DeviceClassCapacitor> (circuit, cn);
     }
-    cls = make_device_class<db::DeviceClassCapacitor> (circuit, cn);
 
     //  Apply multiplier
     value *= mult;
 
   } else if (element == "D") {
 
-    if (cn.empty ()) {
-      cn = "DIODE";
+    if (cls) {
+      if (! dynamic_cast<db::DeviceClassDiode *>(cls)) {
+        error (tl::sprintf (tl::to_string (tr ("Class %s not a diode device class as required by 'D' element")), cn));
+      }
+    } else {
+      if (cn.empty ()) {
+        cn = "DIODE";
+      }
+      cls = make_device_class<db::DeviceClassDiode> (circuit, cn);
     }
-    cls = make_device_class<db::DeviceClassDiode> (circuit, cn);
 
     //  Apply multiplier to "A"
     std::map<std::string, double>::iterator p;
@@ -154,18 +174,30 @@ bool NetlistSpiceReaderDelegate::element (db::Circuit *circuit, const std::strin
 
   } else if (element == "Q") {
 
-    if (nets.size () == 3) {
-      if (cn.empty ()) {
-        cn = "BJT3";
-      }
-      cls = make_device_class<db::DeviceClassBJT3Transistor> (circuit, cn);
-    } else if (nets.size () == 4) {
-      if (cn.empty ()) {
-        cn = "BJT4";
-      }
-      cls = make_device_class<db::DeviceClassBJT4Transistor> (circuit, cn);
-    } else {
+    if (nets.size () != 3 && nets.size () != 4) {
       error (tl::to_string (tr ("'Q' element needs to have 3 or 4 terminals")));
+    } else if (cls) {
+      if (nets.size () == 3) {
+        if (! dynamic_cast<db::DeviceClassBJT3Transistor *>(cls)) {
+          error (tl::sprintf (tl::to_string (tr ("Class %s not a 3-terminal BJT device class as required by 'Q' element")), cn));
+        }
+      } else {
+        if (! dynamic_cast<db::DeviceClassBJT4Transistor *>(cls)) {
+          error (tl::sprintf (tl::to_string (tr ("Class %s not a 4-terminal BJT device class as required by 'Q' element")), cn));
+        }
+      }
+    } else {
+      if (nets.size () == 3) {
+        if (cn.empty ()) {
+          cn = "BJT3";
+        }
+        cls = make_device_class<db::DeviceClassBJT3Transistor> (circuit, cn);
+      } else {
+        if (cn.empty ()) {
+          cn = "BJT4";
+        }
+        cls = make_device_class<db::DeviceClassBJT4Transistor> (circuit, cn);
+      }
     }
 
     //  Apply multiplier to "AE"
@@ -177,22 +209,28 @@ bool NetlistSpiceReaderDelegate::element (db::Circuit *circuit, const std::strin
 
   } else if (element == "M") {
 
-    if (nets.size () == 4) {
-      if (cn.empty ()) {
-        cn = "MOS4";
+    if (cls) {
+      if (! dynamic_cast<db::DeviceClassMOS4Transistor *>(cls)) {
+        error (tl::sprintf (tl::to_string (tr ("Class %s not a 4-terminal MOS device class as required by 'M' element")), cn));
       }
-      cls = make_device_class<db::DeviceClassMOS4Transistor> (circuit, cn);
-
-      //  Apply multiplier to "W"
-      std::map<std::string, double>::iterator p;
-      p = params.find ("W");
-      if (p != params.end ()) {
-        p->second *= mult;
-      }
-
     } else {
-      error (tl::to_string (tr ("'M' element needs to have 4 terminals")));
+      if (nets.size () == 4) {
+        if (cn.empty ()) {
+          cn = "MOS4";
+        }
+        cls = make_device_class<db::DeviceClassMOS4Transistor> (circuit, cn);
+      } else {
+        error (tl::to_string (tr ("'M' element needs to have 4 terminals")));
+      }
     }
+
+    //  Apply multiplier to "W"
+    std::map<std::string, double>::iterator p;
+    p = params.find ("W");
+    if (p != params.end ()) {
+      p->second *= mult;
+    }
+
   } else {
     error (tl::sprintf (tl::to_string (tr ("Not a known element type: '%s'")), element));
   }
diff --git a/src/db/db/dbRecursiveShapeIterator.cc b/src/db/db/dbRecursiveShapeIterator.cc
index e3e571721..bbb6e763e 100644
--- a/src/db/db/dbRecursiveShapeIterator.cc
+++ b/src/db/db/dbRecursiveShapeIterator.cc
@@ -864,10 +864,9 @@ RecursiveShapeIterator::new_cell (RecursiveShapeReceiver *receiver) const
     m_layer = m_layers.front ();
   }
 
-  if (! m_start.empty () && m_start.find (cell_index ()) != m_start.end ()) {
-    set_inactive (false);
-  } else if (! m_stop.empty () && m_stop.find (cell_index ()) != m_stop.end ()) {
-    set_inactive (true);
+  bool new_cell_inactive = is_child_inactive (cell_index ());
+  if (is_inactive () != new_cell_inactive) {
+    set_inactive (new_cell_inactive);
   }
 
   new_layer ();
@@ -975,6 +974,18 @@ RecursiveShapeIterator::is_outside_complex_region (const db::Box &box) const
   }
 }
 
+bool
+RecursiveShapeIterator::is_child_inactive (db::cell_index_type new_child) const
+{
+  bool inactive = is_inactive ();
+  if (! m_start.empty () && m_start.find (new_child) != m_start.end ()) {
+    inactive = false;
+  } else if (! m_stop.empty () && m_stop.find (new_child) != m_stop.end ()) {
+    inactive = true;
+  }
+  return inactive;
+}
+
 void
 RecursiveShapeIterator::push (RecursiveShapeReceiver *receiver)
 {
diff --git a/src/db/db/dbRecursiveShapeIterator.h b/src/db/db/dbRecursiveShapeIterator.h
index 40225b8d1..8dc398b95 100644
--- a/src/db/db/dbRecursiveShapeIterator.h
+++ b/src/db/db/dbRecursiveShapeIterator.h
@@ -704,6 +704,19 @@ public:
    */
   void push (RecursiveShapeReceiver *receiver);
 
+  /**
+   *  @brief Returns a value indicating whether the current cell is inactive (disabled)
+   */
+  bool is_inactive () const
+  {
+    return (reinterpret_cast<size_t> (mp_cell) & size_t (1)) != 0;
+  }
+
+  /**
+   *  @brief Returns a value indicating whether a new child cell of the current cell will be inactive
+   */
+  bool is_child_inactive (db::cell_index_type new_child) const;
+
 private:
   std::vector<unsigned int> m_layers;
   bool m_has_layers;
@@ -760,11 +773,6 @@ private:
 
   bool is_outside_complex_region (const db::Box &box) const;
 
-  bool is_inactive () const
-  {
-    return (reinterpret_cast<size_t> (mp_cell) & size_t (1)) != 0;
-  }
-
   void set_inactive (bool a) const 
   {
     size_t c = reinterpret_cast<size_t> (mp_cell);
diff --git a/src/db/db/dbShapes.cc b/src/db/db/dbShapes.cc
index aef79fa21..dedd81cb2 100644
--- a/src/db/db/dbShapes.cc
+++ b/src/db/db/dbShapes.cc
@@ -174,9 +174,15 @@ Shapes::do_insert (const Shapes &d)
   if (layout () == d.layout ()) {
 
     //  both shape containers reside in the same repository space - simply copy
-    m_layers.reserve (d.m_layers.size ());
-    for (tl::vector<LayerBase *>::const_iterator l = d.m_layers.begin (); l != d.m_layers.end (); ++l) {
-      m_layers.push_back ((*l)->clone (this, manager ()));
+    if (m_layers.empty ()) {
+      m_layers.reserve (d.m_layers.size ());
+      for (tl::vector<LayerBase *>::const_iterator l = d.m_layers.begin (); l != d.m_layers.end (); ++l) {
+        m_layers.push_back ((*l)->clone (this, manager ()));
+      }
+    } else {
+      for (tl::vector<LayerBase *>::const_iterator l = d.m_layers.begin (); l != d.m_layers.end (); ++l) {
+        (*l)->insert_into (this);
+      }
     }
 
   } else if (layout () == 0) {
diff --git a/src/db/db/dbShapes.h b/src/db/db/dbShapes.h
index 311531093..46bc35e3d 100644
--- a/src/db/db/dbShapes.h
+++ b/src/db/db/dbShapes.h
@@ -494,6 +494,7 @@ public:
   virtual void transform_into (Shapes *target, const Trans &trans, GenericRepository &rep, ArrayRepository &array_rep, pm_delegate_type &pm) const = 0;
   virtual void transform_into (Shapes *target, const ICplxTrans &trans, GenericRepository &rep, ArrayRepository &array_rep) const = 0;
   virtual void transform_into (Shapes *target, const ICplxTrans &trans, GenericRepository &rep, ArrayRepository &array_rep, pm_delegate_type &pm) const = 0;
+  virtual void insert_into (Shapes *target) = 0;
   virtual void deref_into (Shapes *target) = 0;
   virtual void deref_into (Shapes *target, pm_delegate_type &pm) = 0;
   virtual void deref_and_transform_into (Shapes *target, const Trans &trans) = 0;
diff --git a/src/db/db/dbShapes2.cc b/src/db/db/dbShapes2.cc
index 73fd33aad..19396588e 100644
--- a/src/db/db/dbShapes2.cc
+++ b/src/db/db/dbShapes2.cc
@@ -834,6 +834,13 @@ layer_class<Sh, StableTag>::transform_into (Shapes *target, const ICplxTrans &tr
   }
 }
 
+template <class Sh, class StableTag>
+void
+layer_class<Sh, StableTag>::insert_into (Shapes *target)
+{
+  target->insert (m_layer.begin (), m_layer.end ());
+}
+
 template <class Sh, class StableTag>
 void 
 layer_class<Sh, StableTag>::deref_into (Shapes *target) 
@@ -870,6 +877,7 @@ layer_class<Sh, StableTag>::deref_and_transform_into (Shapes *target, const Tran
 {
   deref_and_transform_into_shapes deref_op (target);
   for (typename layer_type::iterator s = m_layer.begin (); s != m_layer.end (); ++s) {
+
     deref_op (*s, trans, pm);
   }
 }
diff --git a/src/db/db/dbShapes2.h b/src/db/db/dbShapes2.h
index d60678e28..7c7d3ba60 100644
--- a/src/db/db/dbShapes2.h
+++ b/src/db/db/dbShapes2.h
@@ -149,6 +149,7 @@ public:
   virtual void transform_into (Shapes *target, const Trans &trans, GenericRepository &rep, ArrayRepository &array_rep, pm_delegate_type &pm) const;
   virtual void transform_into (Shapes *target, const ICplxTrans &trans, GenericRepository &rep, ArrayRepository &array_rep) const;
   virtual void transform_into (Shapes *target, const ICplxTrans &trans, GenericRepository &rep, ArrayRepository &array_rep, pm_delegate_type &pm) const;
+  virtual void insert_into (Shapes *target);
   virtual void deref_into (Shapes *target);
   virtual void deref_into (Shapes *target, pm_delegate_type &pm);
   virtual void deref_and_transform_into (Shapes *target, const Trans &trans);
diff --git a/src/db/db/gsiDeclDbCell.cc b/src/db/db/gsiDeclDbCell.cc
index 1ca13c811..5c051852e 100644
--- a/src/db/db/gsiDeclDbCell.cc
+++ b/src/db/db/gsiDeclDbCell.cc
@@ -1491,6 +1491,7 @@ Class<db::Cell> decl_Cell ("db", "Cell",
     "If no property with that key exists, it will create one. Using that method is more "
     "convenient than creating a new property set with a new ID and assigning that properties ID.\n"
     "This method may change the properties ID. "
+    "Note: GDS only supports integer keys. OASIS supports numeric and string keys. "
     "\n"
     "This method has been introduced in version 0.23."
   ) + 
@@ -3453,6 +3454,7 @@ Class<db::Instance> decl_Instance ("db", "Instance",
     "If no property with that key exists, it will create one. Using that method is more "
     "convenient than creating a new property set with a new ID and assigning that properties ID.\n"
     "This method may change the properties ID. "
+    "Note: GDS only supports integer keys. OASIS supports numeric and string keys. "
     "Calling this method may invalidate any iterators. It should not be called inside a "
     "loop iterating over instances.\n"
     "\n"
diff --git a/src/db/db/gsiDeclDbCommonStreamOptions.cc b/src/db/db/gsiDeclDbCommonStreamOptions.cc
index ac2fb3223..32b8ede8c 100644
--- a/src/db/db/gsiDeclDbCommonStreamOptions.cc
+++ b/src/db/db/gsiDeclDbCommonStreamOptions.cc
@@ -25,6 +25,7 @@
 #include "dbCommonReader.h"
 #include "dbLoadLayoutOptions.h"
 #include "gsiDecl.h"
+#include "gsiEnums.h"
 
 namespace dn
 {
@@ -84,6 +85,16 @@ static void set_properties_enabled (db::LoadLayoutOptions *options, bool l)
   options->get_options<db::CommonReaderOptions> ().enable_properties = l;
 }
 
+static db::CommonReader::CellConflictResolution get_cell_conflict_resolution (const db::LoadLayoutOptions *options)
+{
+  return options->get_options<db::CommonReaderOptions> ().cell_conflict_resolution;
+}
+
+static void set_cell_conflict_resolution (db::LoadLayoutOptions *options, db::CommonReader::CellConflictResolution cc)
+{
+  options->get_options<db::CommonReaderOptions> ().cell_conflict_resolution = cc;
+}
+
 //  extend lay::LoadLayoutOptions with the Common options
 static
 gsi::ClassExt<db::LoadLayoutOptions> common_reader_options (
@@ -156,10 +167,56 @@ gsi::ClassExt<db::LoadLayoutOptions> common_reader_options (
     "@param enabled True, if properties should be read."
     "\n"
     "Starting with version 0.25 this option only applies to GDS2 and OASIS format. Other formats provide their own configuration."
+  ) +
+  gsi::method_ext ("cell_conflict_resolution", &get_cell_conflict_resolution,
+    "@brief Gets the cell conflict resolution mode\n"
+    "\n"
+    "Multiple layout files can be collected into a single Layout object by reading file after file into the Layout object. "
+    "Cells with same names are considered a conflict. This mode indicates how such conflicts are resolved. See \\LoadLayoutOptions::CellConflictResolution "
+    "for the values allowed. The default mode is \\LoadLayoutOptions::CellConflictResolution#AddToCell.\n"
+    "\n"
+    "This option has been introduced in version 0.27."
+  ) +
+  gsi::method_ext ("cell_conflict_resolution=", &set_cell_conflict_resolution, gsi::arg ("mode"),
+    "@brief Sets the cell conflict resolution mode\n"
+    "\n"
+    "See \\cell_conflict_resolution for details about this option.\n"
+    "\n"
+    "This option has been introduced in version 0.27."
   ),
   ""
 );
 
+
+gsi::EnumIn<db::LoadLayoutOptions, db::CommonReader::CellConflictResolution> decl_dbCommonReader_CellConflictResolution ("db", "CellConflictResolution",
+  gsi::enum_const ("AddToCell", db::CommonReader::AddToCell,
+    "@brief Add content to existing cell\n"
+    "This is the mode use in before version 0.27. Content of new cells is simply added to existing cells with the same name."
+  ) +
+  gsi::enum_const ("OverwriteCell", db::CommonReader::OverwriteCell,
+    "@brief The old cell is overwritten entirely (including child cells which are not used otherwise)\n"
+  ) +
+  gsi::enum_const ("SkipNewCell", db::CommonReader::SkipNewCell,
+    "@brief The new cell is skipped entirely (including child cells which are not used otherwise)\n"
+  ) +
+  gsi::enum_const ("RenameCell", db::CommonReader::RenameCell,
+    "@brief The new cell will be renamed to become unique\n"
+  ),
+  "@brief This enum specifies how cell conflicts are handled if a layout read into another layout and a cell name conflict arises. "
+  "Until version 0.26.8 and before, the mode was always 'AddToCell'. On reading, a cell was 'reopened' when encountering a cell name "
+  "which already existed. This mode is still the default. The other modes are made available to support other ways of merging layouts.\n"
+  "\n"
+  "Proxy cells are never modified in the existing layout. Proxy cells are always local to their layout file. So if the existing cell is "
+  "a proxy cell, the new cell will be renamed.\n"
+  "\n"
+  "If the new or existing cell is a ghost cell, both cells are merged always.\n"
+  "\n"
+  "This enum was introduced in version 0.27.\n"
+);
+
+//  Inject the NetlistCrossReference::Status declarations into NetlistCrossReference:
+gsi::ClassExt<db::LoadLayoutOptions> inject_CellConflictResolution_in_parent (decl_dbCommonReader_CellConflictResolution.defs ());
+
 }
 
 
diff --git a/src/db/db/gsiDeclDbLayout.cc b/src/db/db/gsiDeclDbLayout.cc
index 79574277b..2e85264b4 100644
--- a/src/db/db/gsiDeclDbLayout.cc
+++ b/src/db/db/gsiDeclDbLayout.cc
@@ -1028,11 +1028,12 @@ Class<db::Layout> decl_Layout ("db", "Layout",
     "This method has been introduced in version 0.24."
   ) + 
   gsi::method_ext ("set_property", &set_layout_property, gsi::arg ("key"), gsi::arg ("value"),
-    "@brief Set the user property with the given key to the given value\n"
+    "@brief Sets the user property with the given key to the given value\n"
     "This method is a convenience method that sets the property with the given key to the given value. "
     "If no property with that key exists, it will create one. Using that method is more "
     "convenient than creating a new property set with a new ID and assigning that properties ID.\n"
     "This method may change the properties ID. "
+    "Note: GDS only supports integer keys. OASIS supports numeric and string keys. "
     "\n"
     "This method has been introduced in version 0.24."
   ) + 
diff --git a/src/db/db/gsiDeclDbShape.cc b/src/db/db/gsiDeclDbShape.cc
index b0ae59e3b..1062c1374 100644
--- a/src/db/db/gsiDeclDbShape.cc
+++ b/src/db/db/gsiDeclDbShape.cc
@@ -1283,6 +1283,7 @@ Class<db::Shape> decl_Shape ("db", "Shape",
     "If no property with that key exists, it will create one. Using that method is more "
     "convenient than creating a new property set with a new ID and assigning that properties ID.\n"
     "This method may change the properties ID. "
+    "Note: GDS only supports integer keys. OASIS supports numeric and string keys. "
     "Calling this method will invalidate any iterators. It should not be called inside a "
     "loop iterating over shapes.\n"
     "\n"
diff --git a/src/db/unit_tests/dbD25TechnologyComponentTests.cc b/src/db/unit_tests/dbD25TechnologyComponentTests.cc
new file mode 100644
index 000000000..181ccb92a
--- /dev/null
+++ b/src/db/unit_tests/dbD25TechnologyComponentTests.cc
@@ -0,0 +1,73 @@
+
+/*
+
+  KLayout Layout Viewer
+  Copyright (C) 2006-2020 Matthias Koefferlein
+
+  This program is free software; you can redistribute it and/or modify
+  it under the terms of the GNU General Public License as published by
+  the Free Software Foundation; either version 2 of the License, or
+  (at your option) any later version.
+
+  This program is distributed in the hope that it will be useful,
+  but WITHOUT ANY WARRANTY; without even the implied warranty of
+  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+  GNU General Public License for more details.
+
+  You should have received a copy of the GNU General Public License
+  along with this program; if not, write to the Free Software
+  Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
+
+*/
+
+
+
+#include "dbD25TechnologyComponent.h"
+#include "tlUnitTest.h"
+
+
+TEST(1)
+{
+  db::D25TechnologyComponent comp;
+
+  comp.compile_from_source ("1/0: 1.0 1.5 # a comment");
+  EXPECT_EQ (comp.to_string (), "1/0: zstart=1, zstop=1.5");
+
+  comp.compile_from_source ("1/0: zstart=1.0 zstop=1.5");
+  EXPECT_EQ (comp.to_string (), "1/0: zstart=1, zstop=1.5");
+
+  comp.compile_from_source ("1/0: zstart=1.0 height=0.5");
+  EXPECT_EQ (comp.to_string (), "1/0: zstart=1, zstop=1.5");
+
+  comp.compile_from_source ("1/0: 1.0 height=0.5");
+  EXPECT_EQ (comp.to_string (), "1/0: zstart=1, zstop=1.5");
+
+  comp.compile_from_source ("1/0: zstop=1.5 height=0.5");
+  EXPECT_EQ (comp.to_string (), "1/0: zstart=1, zstop=1.5");
+
+  comp.compile_from_source ("1/0: zstart=1.0 zstop=1.5\nname: height=3");
+  EXPECT_EQ (comp.to_string (), "1/0: zstart=1, zstop=1.5\nname: zstart=1.5, zstop=4.5");
+
+  comp.compile_from_source ("1/0: zstart=1.0 zstop=1.5\nname: zstart=4.0 height=3\n\n# a comment line");
+  EXPECT_EQ (comp.to_string (), "1/0: zstart=1, zstop=1.5\nname: zstart=4, zstop=7");
+
+  try {
+    comp.compile_from_source ("blabla");
+    EXPECT_EQ (false, true);
+  } catch (...) { }
+
+  try {
+    comp.compile_from_source ("1/0: 1 2 3");
+    EXPECT_EQ (false, true);
+  } catch (...) { }
+
+  try {
+    comp.compile_from_source ("1/0: foo=1 bar=2");
+    EXPECT_EQ (false, true);
+  } catch (...) { }
+
+  try {
+    comp.compile_from_source ("1/0: 1;2");
+    EXPECT_EQ (false, true);
+  } catch (...) { }
+}
diff --git a/src/db/unit_tests/dbHierProcessorTests.cc b/src/db/unit_tests/dbHierProcessorTests.cc
index 11f3bb68a..3d2b12cad 100644
--- a/src/db/unit_tests/dbHierProcessorTests.cc
+++ b/src/db/unit_tests/dbHierProcessorTests.cc
@@ -606,8 +606,8 @@ TEST(BasicAnd9)
     //  from atop the CHILD cell don't interact with shapes inside CHILD, so there are 4 shapes rather than
     //  6. And the shapes from top inside the ring are not seen by the RING's subject shapes.
     "TOP[1] 0 insts, 0 shapes (1 times)\n"
-    "RING[1] 0 insts, 0 shapes (1 times)\n"
     "CHILD1[1] 0 insts, 4 shapes (2 times)\n"
+    "RING[1] 0 insts, 0 shapes (1 times)\n"
   );
 }
 
@@ -622,8 +622,8 @@ TEST(BasicNot9)
     //  from atop the CHILD cell don't interact with shapes inside CHILD, so there are 4 shapes rather than
     //  6. And the shapes from top inside the ring are not seen by the RING's subject shapes.
     "TOP[1] 0 insts, 0 shapes (1 times)\n"
-    "RING[1] 0 insts, 0 shapes (1 times)\n"
     "CHILD1[1] 0 insts, 4 shapes (2 times)\n"
+    "RING[1] 0 insts, 0 shapes (1 times)\n"
   );
 }
 
@@ -746,8 +746,8 @@ TEST(BasicAndWithSize9)
     //  from atop the CHILD cell don't interact with shapes inside CHILD, so there are 4 shapes rather than
     //  6. And the shapes from top inside the ring are not seen by the RING's subject shapes.
     "TOP[1] 0 insts, 0 shapes (1 times)\n"
-    "RING[1] 0 insts, 0 shapes (1 times)\n"
     "CHILD1[1] 0 insts, 6 shapes (2 times)\n"
+    "RING[1] 0 insts, 0 shapes (1 times)\n"
   );
 }
 
@@ -762,8 +762,8 @@ TEST(BasicNotWithSize9)
     //  from atop the CHILD cell don't interact with shapes inside CHILD, so there are 4 shapes rather than
     //  6. And the shapes from top inside the ring are not seen by the RING's subject shapes.
     "TOP[1] 0 insts, 0 shapes (1 times)\n"
-    "RING[1] 0 insts, 0 shapes (1 times)\n"
     "CHILD1[1] 0 insts, 6 shapes (2 times)\n"
+    "RING[1] 0 insts, 0 shapes (1 times)\n"
   );
 }
 
@@ -898,8 +898,8 @@ TEST(TwoInputsAnd9)
     //  from atop the CHILD cell don't interact with shapes inside CHILD, so there are 4 shapes rather than
     //  6. And the shapes from top inside the ring are not seen by the RING's subject shapes.
     "TOP[1] 0 insts, 0 shapes (1 times)\n"
-    "RING[1] 1 insts, 0 shapes (1 times)\n"
     "CHILD1[1] 0 insts, 4 shapes (2 times)\n"
+    "RING[1] 1 insts, 0 shapes (1 times)\n"
   );
 }
 
@@ -914,8 +914,8 @@ TEST(TwoInputsNot9)
     //  from atop the CHILD cell don't interact with shapes inside CHILD, so there are 4 shapes rather than
     //  6. And the shapes from top inside the ring are not seen by the RING's subject shapes.
     "TOP[1] 0 insts, 0 shapes (1 times)\n"
-    "RING[1] 1 insts, 0 shapes (1 times)\n"
     "CHILD1[1] 0 insts, 4 shapes (2 times)\n"
+    "RING[1] 1 insts, 0 shapes (1 times)\n"
   );
 }
 
@@ -1038,8 +1038,8 @@ TEST(TwoInputsAndWithSize9)
     //  from atop the CHILD cell don't interact with shapes inside CHILD, so there are 4 shapes rather than
     //  6. And the shapes from top inside the ring are not seen by the RING's subject shapes.
     "TOP[1] 0 insts, 0 shapes (1 times)\n"
-    "RING[1] 1 insts, 0 shapes (1 times)\n"
     "CHILD1[1] 0 insts, 6 shapes (2 times)\n"
+    "RING[1] 1 insts, 0 shapes (1 times)\n"
   );
 }
 
@@ -1054,8 +1054,8 @@ TEST(TwoInputsNotWithSize9)
     //  from atop the CHILD cell don't interact with shapes inside CHILD, so there are 4 shapes rather than
     //  6. And the shapes from top inside the ring are not seen by the RING's subject shapes.
     "TOP[1] 0 insts, 0 shapes (1 times)\n"
-    "RING[1] 1 insts, 0 shapes (1 times)\n"
     "CHILD1[1] 0 insts, 6 shapes (2 times)\n"
+    "RING[1] 1 insts, 0 shapes (1 times)\n"
   );
 }
 
@@ -1130,8 +1130,8 @@ TEST(BasicSelfOverlap9)
     //  from atop the CHILD cell don't interact with shapes inside CHILD, so there are 4 shapes rather than
     //  6. And the shapes from top inside the ring are not seen by the RING's subject shapes.
     "TOP[1] 0 insts, 0 shapes (1 times)\n"
-    "RING[1] 0 insts, 1 shapes (1 times)\n"
     "CHILD1[1] 0 insts, 4 shapes (2 times)\n"
+    "RING[1] 0 insts, 1 shapes (1 times)\n"
   );
 }
 
@@ -1200,8 +1200,8 @@ TEST(BasicSelfOverlapWithSize9)
     //  from atop the CHILD cell don't interact with shapes inside CHILD, so there are 4 shapes rather than
     //  6. And the shapes from top inside the ring are not seen by the RING's subject shapes.
     "TOP[1] 0 insts, 0 shapes (1 times)\n"
-    "RING[1] 0 insts, 1 shapes (1 times)\n"
     "CHILD1[1] 0 insts, 6 shapes (2 times)\n"
+    "RING[1] 0 insts, 1 shapes (1 times)\n"
   );
 }
 
diff --git a/src/db/unit_tests/dbLayoutToNetlistTests.cc b/src/db/unit_tests/dbLayoutToNetlistTests.cc
index 3e886b16a..b2feaff2a 100644
--- a/src/db/unit_tests/dbLayoutToNetlistTests.cc
+++ b/src/db/unit_tests/dbLayoutToNetlistTests.cc
@@ -3156,3 +3156,232 @@ TEST(12_FlattenCircuitDoesFlattenLayout)
   db::compare_layouts (_this, ly, au);
 }
 
+TEST(13_JoinNets)
+{
+  db::Layout ly;
+  db::LayerMap lmap;
+
+  unsigned int nwell      = define_layer (ly, lmap, 1);
+  unsigned int active     = define_layer (ly, lmap, 2);
+  unsigned int pplus      = define_layer (ly, lmap, 10);
+  unsigned int nplus      = define_layer (ly, lmap, 11);
+  unsigned int poly       = define_layer (ly, lmap, 3);
+  unsigned int poly_lbl   = define_layer (ly, lmap, 3, 1);
+  unsigned int diff_cont  = define_layer (ly, lmap, 4);
+  unsigned int poly_cont  = define_layer (ly, lmap, 5);
+  unsigned int metal1     = define_layer (ly, lmap, 6);
+  unsigned int metal1_lbl = define_layer (ly, lmap, 6, 1);
+  unsigned int via1       = define_layer (ly, lmap, 7);
+  unsigned int metal2     = define_layer (ly, lmap, 8);
+  unsigned int metal2_lbl = define_layer (ly, lmap, 8, 1);
+
+  {
+    db::LoadLayoutOptions options;
+    options.get_options<db::CommonReaderOptions> ().layer_map = lmap;
+    options.get_options<db::CommonReaderOptions> ().create_other_layers = false;
+
+    std::string fn (tl::testsrc ());
+    fn = tl::combine_path (fn, "testdata");
+    fn = tl::combine_path (fn, "algo");
+    fn = tl::combine_path (fn, "device_extract_l13.gds");
+
+    tl::InputStream stream (fn);
+    db::Reader reader (stream);
+    reader.read (ly, options);
+  }
+
+  db::Cell &tc = ly.cell (*ly.begin_top_down ());
+  db::LayoutToNetlist l2n (db::RecursiveShapeIterator (ly, tc, std::set<unsigned int> ()));
+
+  std::auto_ptr<db::Region> rbulk (l2n.make_layer ("bulk"));
+  std::auto_ptr<db::Region> rnwell (l2n.make_layer (nwell, "nwell"));
+  std::auto_ptr<db::Region> ractive (l2n.make_layer (active, "active"));
+  std::auto_ptr<db::Region> rpplus (l2n.make_layer (pplus, "pplus"));
+  std::auto_ptr<db::Region> rnplus (l2n.make_layer (nplus, "nplus"));
+  std::auto_ptr<db::Region> rpoly (l2n.make_polygon_layer (poly, "poly"));
+  std::auto_ptr<db::Texts> rpoly_lbl (l2n.make_text_layer (poly_lbl, "poly_lbl"));
+  std::auto_ptr<db::Region> rdiff_cont (l2n.make_polygon_layer (diff_cont, "diff_cont"));
+  std::auto_ptr<db::Region> rpoly_cont (l2n.make_polygon_layer (poly_cont, "poly_cont"));
+  std::auto_ptr<db::Region> rmetal1 (l2n.make_polygon_layer (metal1, "metal1"));
+  std::auto_ptr<db::Texts> rmetal1_lbl (l2n.make_text_layer (metal1_lbl, "metal1_lbl"));
+  std::auto_ptr<db::Region> rvia1 (l2n.make_polygon_layer (via1, "via1"));
+  std::auto_ptr<db::Region> rmetal2 (l2n.make_polygon_layer (metal2, "metal2"));
+  std::auto_ptr<db::Texts> rmetal2_lbl (l2n.make_text_layer (metal2_lbl, "metal2_lbl"));
+
+  //  derived regions
+
+  db::Region ractive_in_nwell = *ractive & *rnwell;
+  db::Region rpactive = ractive_in_nwell & *rpplus;
+  db::Region rntie    = ractive_in_nwell & *rnplus;
+  db::Region rpgate   = rpactive & *rpoly;
+  db::Region rpsd     = rpactive - rpgate;
+
+  db::Region ractive_outside_nwell = *ractive - *rnwell;
+  db::Region rnactive = ractive_outside_nwell & *rnplus;
+  db::Region rptie    = ractive_outside_nwell & *rpplus;
+  db::Region rngate   = rnactive & *rpoly;
+  db::Region rnsd     = rnactive - rngate;
+
+  //  return the computed layers into the original layout and write it for debugging purposes
+
+  unsigned int lgate  = ly.insert_layer (db::LayerProperties (20, 0));      // 20/0 -> Gate
+  unsigned int lsd    = ly.insert_layer (db::LayerProperties (21, 0));      // 21/0 -> Source/Drain
+  unsigned int lpdiff = ly.insert_layer (db::LayerProperties (22, 0));      // 22/0 -> P Diffusion
+  unsigned int lndiff = ly.insert_layer (db::LayerProperties (23, 0));      // 23/0 -> N Diffusion
+  unsigned int lptie  = ly.insert_layer (db::LayerProperties (24, 0));      // 24/0 -> P Tie
+  unsigned int lntie  = ly.insert_layer (db::LayerProperties (25, 0));      // 25/0 -> N Tie
+
+  rpgate.insert_into (&ly, tc.cell_index (), lgate);
+  rngate.insert_into (&ly, tc.cell_index (), lgate);
+  rpsd.insert_into (&ly, tc.cell_index (), lsd);
+  rnsd.insert_into (&ly, tc.cell_index (), lsd);
+  rpsd.insert_into (&ly, tc.cell_index (), lpdiff);
+  rnsd.insert_into (&ly, tc.cell_index (), lndiff);
+  rpsd.insert_into (&ly, tc.cell_index (), lptie);
+  rnsd.insert_into (&ly, tc.cell_index (), lntie);
+
+  db::NetlistDeviceExtractorMOS4Transistor pmos_ex ("PMOS");
+  db::NetlistDeviceExtractorMOS4Transistor nmos_ex ("NMOS");
+
+  //  device extraction
+
+  db::NetlistDeviceExtractor::input_layers dl;
+
+  dl["SD"] = &rpsd;
+  dl["G"] = &rpgate;
+  dl["P"] = rpoly.get ();  //  not needed for extraction but to return terminal shapes
+  dl["W"] = rnwell.get ();
+  l2n.extract_devices (pmos_ex, dl);
+
+  dl["SD"] = &rnsd;
+  dl["G"] = &rngate;
+  dl["P"] = rpoly.get ();  //  not needed for extraction but to return terminal shapes
+  dl["W"] = rbulk.get ();
+  l2n.extract_devices (nmos_ex, dl);
+
+  //  net extraction
+
+  l2n.register_layer (rpsd, "psd");
+  l2n.register_layer (rnsd, "nsd");
+  l2n.register_layer (rptie, "ptie");
+  l2n.register_layer (rntie, "ntie");
+
+  //  Intra-layer
+  l2n.connect (rpsd);
+  l2n.connect (rnsd);
+  l2n.connect (*rnwell);
+  l2n.connect (*rpoly);
+  l2n.connect (*rdiff_cont);
+  l2n.connect (*rpoly_cont);
+  l2n.connect (*rmetal1);
+  l2n.connect (*rvia1);
+  l2n.connect (*rmetal2);
+  l2n.connect (rptie);
+  l2n.connect (rntie);
+  //  Inter-layer
+  l2n.connect (rpsd,        *rdiff_cont);
+  l2n.connect (rnsd,        *rdiff_cont);
+  l2n.connect (*rpoly,      *rpoly_cont);
+  l2n.connect (*rpoly_cont, *rmetal1);
+  l2n.connect (*rdiff_cont, *rmetal1);
+  l2n.connect (*rdiff_cont, rptie);
+  l2n.connect (*rdiff_cont, rntie);
+  l2n.connect (*rnwell,     rntie);
+  l2n.connect (*rmetal1,    *rvia1);
+  l2n.connect (*rvia1,      *rmetal2);
+  l2n.connect (*rpoly,      *rpoly_lbl);     //  attaches labels
+  l2n.connect (*rmetal1,    *rmetal1_lbl);   //  attaches labels
+  l2n.connect (*rmetal2,    *rmetal2_lbl);   //  attaches labels
+  //  Global
+  l2n.connect_global (rntie, "VDD");
+  l2n.connect_global (*rnwell, "VDD");
+  l2n.connect_global (rptie, "VSS");
+  l2n.connect_global (*rbulk, "VSS");
+
+  //  Extract with joining VSS and VDD
+  l2n.extract_netlist ("{VSS,VDD}");
+
+  //  debug layers produced for nets
+  //    201/0 -> Well
+  //    203/0 -> Poly
+  //    204/0 -> Diffusion contacts
+  //    205/0 -> Poly contacts
+  //    206/0 -> Metal1
+  //    207/0 -> Via1
+  //    208/0 -> Metal2
+  //    210/0 -> N source/drain
+  //    211/0 -> P source/drain
+  //    212/0 -> N tie
+  //    213/0 -> P tie
+  std::map<const db::Region *, unsigned int> dump_map;
+  dump_map [&rpsd            ] = ly.insert_layer (db::LayerProperties (210, 0));
+  dump_map [&rnsd            ] = ly.insert_layer (db::LayerProperties (211, 0));
+  dump_map [&rptie           ] = ly.insert_layer (db::LayerProperties (212, 0));
+  dump_map [&rntie           ] = ly.insert_layer (db::LayerProperties (213, 0));
+  dump_map [rbulk.get ()     ] = ly.insert_layer (db::LayerProperties (214, 0));
+  dump_map [rnwell.get ()    ] = ly.insert_layer (db::LayerProperties (201, 0));
+  dump_map [rpoly.get ()     ] = ly.insert_layer (db::LayerProperties (203, 0));
+  dump_map [rdiff_cont.get ()] = ly.insert_layer (db::LayerProperties (204, 0));
+  dump_map [rpoly_cont.get ()] = ly.insert_layer (db::LayerProperties (205, 0));
+  dump_map [rmetal1.get ()   ] = ly.insert_layer (db::LayerProperties (206, 0));
+  dump_map [rvia1.get ()     ] = ly.insert_layer (db::LayerProperties (207, 0));
+  dump_map [rmetal2.get ()   ] = ly.insert_layer (db::LayerProperties (208, 0));
+
+  //  write nets to layout
+  db::CellMapping cm = l2n.cell_mapping_into (ly, tc);
+  dump_nets_to_layout (l2n, ly, dump_map, cm);
+
+  dump_map.clear ();
+  dump_map [&rpsd            ] = ly.insert_layer (db::LayerProperties (310, 0));
+  dump_map [&rnsd            ] = ly.insert_layer (db::LayerProperties (311, 0));
+  dump_map [&rptie           ] = ly.insert_layer (db::LayerProperties (312, 0));
+  dump_map [&rntie           ] = ly.insert_layer (db::LayerProperties (313, 0));
+  dump_map [rbulk.get ()     ] = ly.insert_layer (db::LayerProperties (314, 0));
+  dump_map [rnwell.get ()    ] = ly.insert_layer (db::LayerProperties (301, 0));
+  dump_map [rpoly.get ()     ] = ly.insert_layer (db::LayerProperties (303, 0));
+  dump_map [rdiff_cont.get ()] = ly.insert_layer (db::LayerProperties (304, 0));
+  dump_map [rpoly_cont.get ()] = ly.insert_layer (db::LayerProperties (305, 0));
+  dump_map [rmetal1.get ()   ] = ly.insert_layer (db::LayerProperties (306, 0));
+  dump_map [rvia1.get ()     ] = ly.insert_layer (db::LayerProperties (307, 0));
+  dump_map [rmetal2.get ()   ] = ly.insert_layer (db::LayerProperties (308, 0));
+
+  dump_recursive_nets_to_layout (l2n, ly, dump_map, cm);
+
+  //  compare netlist as string
+  CHECKPOINT ();
+  db::compare_netlist (_this, *l2n.netlist (),
+    "circuit RINGO ();\n"
+    "  subcircuit INV2 $1 (IN=$I7,$2=FB,OUT=OSC,$4=VSS,$5=VDD,VDD=VDD,VSS=VSS);\n"
+    "  subcircuit INV2 $2 (IN=FB,$2=$I34,OUT=$I17,$4=VSS,$5=VDD,VDD=VDD,VSS=VSS);\n"
+    "  subcircuit INV2 $3 (IN=$3,$2=$I38,OUT=$I4,$4=VSS,$5=VDD,VDD=VDD,VSS=VSS);\n"
+    "  subcircuit INV2 $4 (IN=$I2,$2=$I37,OUT=$3,$4=VSS,$5=VDD,VDD=VDD,VSS=VSS);\n"
+    "  subcircuit INV2 $5 (IN=$I4,$2=$I39,OUT=$I5,$4=VSS,$5=VDD,VDD=VDD,VSS=VSS);\n"
+    "  subcircuit INV2 $6 (IN=$I5,$2=$I40,OUT=$I6,$4=VSS,$5=VDD,VDD=VDD,VSS=VSS);\n"
+    "  subcircuit INV2 $7 (IN=$I6,$2=$I41,OUT=$I7,$4=VSS,$5=VDD,VDD=VDD,VSS=VSS);\n"
+    "  subcircuit INV2 $8 (IN=$I17,$2=$I35,OUT=$I1,$4=VSS,$5=VDD,VDD=VDD,VSS=VSS);\n"
+    "  subcircuit INV2 $9 (IN=$I1,$2=$I36,OUT=$I2,$4=VSS,$5=VDD,VDD=VDD,VSS=VSS);\n"
+    "end;\n"
+    "circuit INV2 (IN=IN,$2=$2,OUT=OUT,$4=$4,$5=$5,VDD=VDD,VSS=VSS);\n"
+    "  device PMOS $1 (S=$2,G=IN,D=$5,B=VDD) (L=0.25,W=0.95,AS=0.49875,AD=0.26125,PS=2.95,PD=1.5);\n"
+    "  device PMOS $2 (S=$5,G=$2,D=OUT,B=VDD) (L=0.25,W=0.95,AS=0.26125,AD=0.49875,PS=1.5,PD=2.95);\n"
+    "  device NMOS $3 (S=$2,G=IN,D=$4,B=VSS) (L=0.25,W=0.95,AS=0.49875,AD=0.26125,PS=2.95,PD=1.5);\n"
+    "  device NMOS $4 (S=$4,G=$2,D=OUT,B=VSS) (L=0.25,W=0.95,AS=0.26125,AD=0.49875,PS=1.5,PD=2.95);\n"
+    "  subcircuit TRANS $1 ($1=$2,$2=$4,$3=IN);\n"
+    "  subcircuit TRANS $2 ($1=$2,$2=$5,$3=IN);\n"
+    "  subcircuit TRANS $3 ($1=$5,$2=OUT,$3=$2);\n"
+    "  subcircuit TRANS $4 ($1=$4,$2=OUT,$3=$2);\n"
+    "end;\n"
+    "circuit TRANS ($1=$1,$2=$2,$3=$3);\n"
+    "end;\n"
+  );
+
+  //  compare the collected test data
+
+  std::string au = tl::testsrc ();
+  au = tl::combine_path (au, "testdata");
+  au = tl::combine_path (au, "algo");
+  au = tl::combine_path (au, "device_extract_au13_circuits.gds");
+
+  db::compare_layouts (_this, ly, au);
+}
+
diff --git a/src/db/unit_tests/dbNetlistReaderTests.cc b/src/db/unit_tests/dbNetlistReaderTests.cc
index 12f0a97f6..4e4779588 100644
--- a/src/db/unit_tests/dbNetlistReaderTests.cc
+++ b/src/db/unit_tests/dbNetlistReaderTests.cc
@@ -359,28 +359,75 @@ TEST(9_DeviceMultipliers)
 
   std::string path = tl::combine_path (tl::combine_path (tl::combine_path (tl::testsrc (), "testdata"), "algo"), "nreader9.cir");
 
-  db::NetlistSpiceReader reader;
-  tl::InputStream is (path);
-  reader.read (is, nl);
+  {
+    db::NetlistSpiceReader reader;
+    tl::InputStream is (path);
+    reader.read (is, nl);
 
-  std::string nl_string = nl.to_string ();
-  //  normalization of exponential representation:
-  nl_string = tl::replaced (nl_string, "e-009", "e-09");
+    std::string nl_string = nl.to_string ();
+    //  normalization of exponential representation:
+    nl_string = tl::replaced (nl_string, "e-009", "e-09");
 
-  EXPECT_EQ (nl_string,
-    "circuit .TOP ();\n"
-    "  device RES $1 (A='1',B='2') (R=850,L=0,W=0,A=0,P=0);\n"
-    "  device RES $2 (A='3',B='4') (R=1700,L=0,W=0,A=0,P=0);\n"
-    "  device NMOS $1 (S='1',G='2',D='3',B='4') (L=7,W=4,AS=0,AD=0,PS=0,PD=0);\n"
-    "  device PMOS $2 (S='1',G='2',D='3',B='4') (L=7,W=2,AS=0,AD=0,PS=0,PD=0);\n"
-    "  device CAP $1 (A='1',B='2') (C=2e-09,A=0,P=0);\n"
-    "  device CAP $2 (A='3',B='4') (C=1e-09,A=0,P=0);\n"
-    "  device DIODE $1 (A='1',C='2') (A=20,P=0);\n"
-    "  device DIODE $2 (A='3',C='4') (A=10,P=0);\n"
-    "  device BIP $1 (C='1',B='2',E='3',S='4') (AE=20,PE=0,AB=0,PB=0,AC=0,PC=0,NE=1);\n"
-    "  device BIP $2 (C='1',B='2',E='3',S='4') (AE=10,PE=0,AB=0,PB=0,AC=0,PC=0,NE=1);\n"
-    "end;\n"
-  );
+    EXPECT_EQ (nl_string,
+      "circuit .TOP ();\n"
+      "  device RES $1 (A='1',B='2') (R=850,L=0,W=0,A=0,P=0);\n"
+      "  device RES $2 (A='3',B='4') (R=1700,L=0,W=0,A=0,P=0);\n"
+      "  device RMODEL $3 (A='1',B='2') (R=850,L=0,W=0,A=0,P=0);\n"
+      "  device RMODEL $4 (A='3',B='4') (R=1700,L=0,W=0,A=0,P=0);\n"
+      "  device NMOS $1 (S='1',G='2',D='3',B='4') (L=7,W=4,AS=0,AD=0,PS=0,PD=0);\n"
+      "  device PMOS $2 (S='1',G='2',D='3',B='4') (L=7,W=2,AS=0,AD=0,PS=0,PD=0);\n"
+      "  device CAP $1 (A='1',B='2') (C=2e-09,A=0,P=0);\n"
+      "  device CAP $2 (A='3',B='4') (C=1e-09,A=0,P=0);\n"
+      "  device CMODEL $3 (A='1',B='2') (C=2e-09,A=0,P=0);\n"
+      "  device CMODEL $4 (A='3',B='4') (C=1e-09,A=0,P=0);\n"
+      "  device IND $1 (A='1',B='2') (L=5e-10);\n"
+      "  device IND $2 (A='3',B='4') (L=1e-09);\n"
+      "  device LMODEL $3 (A='1',B='2') (L=5e-10);\n"
+      "  device LMODEL $4 (A='3',B='4') (L=1e-09);\n"
+      "  device DIODE $1 (A='1',C='2') (A=20,P=0);\n"
+      "  device DIODE $2 (A='3',C='4') (A=10,P=0);\n"
+      "  device BIP $1 (C='1',B='2',E='3',S='4') (AE=20,PE=0,AB=0,PB=0,AC=0,PC=0,NE=1);\n"
+      "  device BIP $2 (C='1',B='2',E='3',S='4') (AE=10,PE=0,AB=0,PB=0,AC=0,PC=0,NE=1);\n"
+      "end;\n"
+    );
+  }
+
+  db::Circuit *top = nl.circuit_by_name (".TOP");
+  nl.remove_circuit (top);
+
+  //  read once again, this time with known classes (must not trigger issue-652)
+  {
+    db::NetlistSpiceReader reader;
+    tl::InputStream is (path);
+    reader.read (is, nl);
+
+    std::string nl_string = nl.to_string ();
+    //  normalization of exponential representation:
+    nl_string = tl::replaced (nl_string, "e-009", "e-09");
+
+    EXPECT_EQ (nl_string,
+      "circuit .TOP ();\n"
+      "  device RES $1 (A='1',B='2') (R=850,L=0,W=0,A=0,P=0);\n"
+      "  device RES $2 (A='3',B='4') (R=1700,L=0,W=0,A=0,P=0);\n"
+      "  device RMODEL $3 (A='1',B='2') (R=850,L=0,W=0,A=0,P=0);\n"
+      "  device RMODEL $4 (A='3',B='4') (R=1700,L=0,W=0,A=0,P=0);\n"
+      "  device NMOS $1 (S='1',G='2',D='3',B='4') (L=7,W=4,AS=0,AD=0,PS=0,PD=0);\n"
+      "  device PMOS $2 (S='1',G='2',D='3',B='4') (L=7,W=2,AS=0,AD=0,PS=0,PD=0);\n"
+      "  device CAP $1 (A='1',B='2') (C=2e-09,A=0,P=0);\n"
+      "  device CAP $2 (A='3',B='4') (C=1e-09,A=0,P=0);\n"
+      "  device CMODEL $3 (A='1',B='2') (C=2e-09,A=0,P=0);\n"
+      "  device CMODEL $4 (A='3',B='4') (C=1e-09,A=0,P=0);\n"
+      "  device IND $1 (A='1',B='2') (L=5e-10);\n"
+      "  device IND $2 (A='3',B='4') (L=1e-09);\n"
+      "  device LMODEL $3 (A='1',B='2') (L=5e-10);\n"
+      "  device LMODEL $4 (A='3',B='4') (L=1e-09);\n"
+      "  device DIODE $1 (A='1',C='2') (A=20,P=0);\n"
+      "  device DIODE $2 (A='3',C='4') (A=10,P=0);\n"
+      "  device BIP $1 (C='1',B='2',E='3',S='4') (AE=20,PE=0,AB=0,PB=0,AC=0,PC=0,NE=1);\n"
+      "  device BIP $2 (C='1',B='2',E='3',S='4') (AE=10,PE=0,AB=0,PB=0,AC=0,PC=0,NE=1);\n"
+      "end;\n"
+    );
+  }
 }
 
 TEST(10_SubcircuitsNoPins)
diff --git a/src/db/unit_tests/unit_tests.pro b/src/db/unit_tests/unit_tests.pro
index d2753f09a..4efc7e5ad 100644
--- a/src/db/unit_tests/unit_tests.pro
+++ b/src/db/unit_tests/unit_tests.pro
@@ -34,6 +34,7 @@ SOURCES = \
     dbPolygonToolsTests.cc \
     dbTechnologyTests.cc \
     dbStreamLayerTests.cc \
+    dbD25TechnologyComponentTests.cc \
     dbVectorTests.cc \
     dbVariableWidthPathTests.cc \
     dbTransTests.cc \
diff --git a/src/drc/drc/built-in-macros/_drc_engine.rb b/src/drc/drc/built-in-macros/_drc_engine.rb
index 62bf78dfc..bcacad3f0 100644
--- a/src/drc/drc/built-in-macros/_drc_engine.rb
+++ b/src/drc/drc/built-in-macros/_drc_engine.rb
@@ -1352,7 +1352,7 @@ module DRC
     # @/code
     #
     # (Technically, the cheat code block is a Ruby Proc and cannot create variables
-    # outside it's scope. Hence the results of this code block have to be passed
+    # outside its scope. Hence the results of this code block have to be passed
     # through the "cheat" method).
     # 
     # To apply cheats for device extraction, use the following scheme:
@@ -2003,7 +2003,7 @@ CODE
         
         sel.each do |s|
           if s == "-"
-            iter.unselect_cells(cell.cell_index)
+            iter.unselect_cells([cell_index])
           elsif s == "-*"
             iter.unselect_all_cells
           elsif s == "+*"
diff --git a/src/drc/drc/built-in-macros/_drc_netter.rb b/src/drc/drc/built-in-macros/_drc_netter.rb
index 2c32640ad..657892e95 100644
--- a/src/drc/drc/built-in-macros/_drc_netter.rb
+++ b/src/drc/drc/built-in-macros/_drc_netter.rb
@@ -162,7 +162,7 @@ module DRC
     # @li \global#capacitor_with_bulk - A capacitor with a separate bulk terminal @/li
     # @/ul
     #
-    # Each device class (e.g. n-MOS/p-MOS or high Vt/low Vt) needs it's own instance
+    # Each device class (e.g. n-MOS/p-MOS or high Vt/low Vt) needs its own instance
     # of device extractor. The device extractor beside the algorithm and specific 
     # extraction settings defines the name of the device to be built.
     #
diff --git a/src/drc/drc/built-in-macros/_drc_source.rb b/src/drc/drc/built-in-macros/_drc_source.rb
index c7c846692..8793e93de 100644
--- a/src/drc/drc/built-in-macros/_drc_source.rb
+++ b/src/drc/drc/built-in-macros/_drc_source.rb
@@ -22,14 +22,27 @@ module DRC
       @layout_var = layout_var
       @path = path
       @cell = cell
-      @inside = nil
       @box = nil
-      @layers = nil
       @sel = []
       @clip = false
       @overlapping = false
       @tmp_layers = []
     end
+
+    # Conceptual deep copy (not including the temp layers)
+    def dup
+      d = DRCSource::new(@engine, @layout, @layout_var, @cell, @path)
+      d._init_internal(@box ? @box.dup : nil, @sel.dup, @clip, @overlapping)
+      d
+    end
+
+    # internal copy initialization
+    def _init_internal(box, sel, clip, overlapping)
+      @box = box
+      @sel = sel
+      @clip = clip
+      @overlapping = overlapping
+    end
         
     # %DRC%
     # @name layout
@@ -139,19 +152,34 @@ module DRC
     # code:
     #
     # @code
-    # layout_with_selection = layout.select("-TOP", "+B")
-    # l1 = layout_with_selection.input(1, 0)
+    # layout_with_selection = source.select("-TOP", "+B")
+    # l1 = source.input(1, 0)
     # ...
     # @/code
     #
     # Please note that the sample above will deliver the children of "B" because there is 
-    # nothing said about how to proceed with cells other than "TOP" or "B".
-    # The following code will just select "B" without it's children, because in the 
+    # nothing said about how to proceed with cells other than "TOP" or "B". Conceptually,
+    # the instantiation path of a cell will be matched against the different filters in the
+    # order they are given.
+    # A matching negative expression will disable the cell, a matching positive expression
+    # will enable the cell. Hence, every cell that has a "B" in the instantiation path 
+    # is enabled.
+    #
+    # The following code will just select "B" without its children, because in the 
     # first "-*" selection, all cells including the children of "B" are disabled:
     #
     # @code
-    # layout_with_selection = layout.select("-*", "+B")
-    # l1 = layout_with_selection.input(1, 0)
+    # layout_with_selection = source.select("-*", "+B")
+    # l1 = source.input(1, 0)
+    # ...
+    # @/code
+    # 
+    # The short form "-" will disable the top cell. This code is identical to the first example
+    # and will start with a disabled top cell regardless of its name:
+    # 
+    # @code
+    # layout_with_selection = source.select("-", "+B")
+    # l1 = source.input(1, 0)
     # ...
     # @/code
     
diff --git a/src/drc/unit_tests/drcSimpleTests.cc b/src/drc/unit_tests/drcSimpleTests.cc
index 46abfdfe1..3cba9b295 100644
--- a/src/drc/unit_tests/drcSimpleTests.cc
+++ b/src/drc/unit_tests/drcSimpleTests.cc
@@ -756,6 +756,47 @@ TEST(16_issue570)
   db::compare_layouts (_this, layout, au, db::NoNormalization);
 }
 
+//  Problems with Source#select
+TEST(17_issue570)
+{
+  std::string rs = tl::testsrc ();
+  rs += "/testdata/drc/drcSimpleTests_17.drc";
+
+  std::string input = tl::testsrc ();
+  input += "/testdata/drc/drcSimpleTests_17.gds";
+
+  std::string au = tl::testsrc ();
+  au += "/testdata/drc/drcSimpleTests_au17.gds";
+
+  std::string output = this->tmp_file ("tmp.gds");
+
+  {
+    //  Set some variables
+    lym::Macro config;
+    config.set_text (tl::sprintf (
+        "$drc_test_source = '%s'\n"
+        "$drc_test_target = '%s'\n"
+      , input, output)
+    );
+    config.set_interpreter (lym::Macro::Ruby);
+    EXPECT_EQ (config.run (), 0);
+  }
+
+  lym::Macro drc;
+  drc.load_from (rs);
+  EXPECT_EQ (drc.run (), 0);
+
+  db::Layout layout;
+
+  {
+    tl::InputStream stream (output);
+    db::Reader reader (stream);
+    reader.read (layout);
+  }
+
+  db::compare_layouts (_this, layout, au, db::NoNormalization);
+}
+
 TEST(18_forget)
 {
   std::string rs = tl::testsrc ();
diff --git a/src/edt/edt/AlignOptionsDialog.ui b/src/edt/edt/AlignOptionsDialog.ui
index 13d218095..c2002f0db 100644
--- a/src/edt/edt/AlignOptionsDialog.ui
+++ b/src/edt/edt/AlignOptionsDialog.ui
@@ -1,7 +1,8 @@
-<ui version="4.0" >
+<?xml version="1.0" encoding="UTF-8"?>
+<ui version="4.0">
  <class>AlignOptionsDialog</class>
- <widget class="QDialog" name="AlignOptionsDialog" >
-  <property name="geometry" >
+ <widget class="QDialog" name="AlignOptionsDialog">
+  <property name="geometry">
    <rect>
     <x>0</x>
     <y>0</y>
@@ -9,26 +10,26 @@
     <height>392</height>
    </rect>
   </property>
-  <property name="windowTitle" >
+  <property name="windowTitle">
    <string>Alignment Options</string>
   </property>
-  <layout class="QVBoxLayout" name="verticalLayout" >
+  <layout class="QVBoxLayout" name="verticalLayout">
    <item>
-    <widget class="QGroupBox" name="groupBox" >
-     <property name="title" >
+    <widget class="QGroupBox" name="groupBox">
+     <property name="title">
       <string>Horizontal alignment</string>
      </property>
-     <layout class="QGridLayout" name="gridLayout_3" >
-      <item row="0" column="0" >
-       <widget class="QRadioButton" name="h_none_rb" >
-        <property name="text" >
+     <layout class="QGridLayout" name="gridLayout_3">
+      <item row="0" column="0">
+       <widget class="QRadioButton" name="h_none_rb">
+        <property name="text">
          <string/>
         </property>
-        <property name="icon" >
-         <iconset resource="layResources.qrc" >
+        <property name="icon">
+         <iconset resource="../../lay/lay/layResources.qrc">
           <normaloff>:/align_none.png</normaloff>:/align_none.png</iconset>
         </property>
-        <property name="iconSize" >
+        <property name="iconSize">
          <size>
           <width>32</width>
           <height>32</height>
@@ -36,16 +37,16 @@
         </property>
        </widget>
       </item>
-      <item row="0" column="2" >
-       <widget class="QRadioButton" name="h_left_rb" >
-        <property name="text" >
+      <item row="0" column="2">
+       <widget class="QRadioButton" name="h_left_rb">
+        <property name="text">
          <string/>
         </property>
-        <property name="icon" >
-         <iconset resource="layResources.qrc" >
+        <property name="icon">
+         <iconset resource="../../lay/lay/layResources.qrc">
           <normaloff>:/align_left.png</normaloff>:/align_left.png</iconset>
         </property>
-        <property name="iconSize" >
+        <property name="iconSize">
          <size>
           <width>32</width>
           <height>32</height>
@@ -53,16 +54,16 @@
         </property>
        </widget>
       </item>
-      <item row="0" column="4" >
-       <widget class="QRadioButton" name="h_center_rb" >
-        <property name="text" >
+      <item row="0" column="4">
+       <widget class="QRadioButton" name="h_center_rb">
+        <property name="text">
          <string/>
         </property>
-        <property name="icon" >
-         <iconset resource="layResources.qrc" >
+        <property name="icon">
+         <iconset resource="../../lay/lay/layResources.qrc">
           <normaloff>:/align_hcenter.png</normaloff>:/align_hcenter.png</iconset>
         </property>
-        <property name="iconSize" >
+        <property name="iconSize">
          <size>
           <width>32</width>
           <height>32</height>
@@ -70,16 +71,16 @@
         </property>
        </widget>
       </item>
-      <item row="0" column="6" >
-       <widget class="QRadioButton" name="h_right_rb" >
-        <property name="text" >
+      <item row="0" column="6">
+       <widget class="QRadioButton" name="h_right_rb">
+        <property name="text">
          <string/>
         </property>
-        <property name="icon" >
-         <iconset resource="layResources.qrc" >
+        <property name="icon">
+         <iconset resource="../../lay/lay/layResources.qrc">
           <normaloff>:/align_right.png</normaloff>:/align_right.png</iconset>
         </property>
-        <property name="iconSize" >
+        <property name="iconSize">
          <size>
           <width>32</width>
           <height>32</height>
@@ -87,12 +88,12 @@
         </property>
        </widget>
       </item>
-      <item row="0" column="7" >
-       <spacer name="horizontalSpacer_3" >
-        <property name="orientation" >
+      <item row="0" column="7">
+       <spacer name="horizontalSpacer_3">
+        <property name="orientation">
          <enum>Qt::Horizontal</enum>
         </property>
-        <property name="sizeHint" stdset="0" >
+        <property name="sizeHint" stdset="0">
          <size>
           <width>243</width>
           <height>20</height>
@@ -100,55 +101,55 @@
         </property>
        </spacer>
       </item>
-      <item row="1" column="0" >
-       <widget class="QLabel" name="label_5" >
-        <property name="text" >
+      <item row="1" column="0">
+       <widget class="QLabel" name="label_5">
+        <property name="text">
          <string>none</string>
         </property>
-        <property name="alignment" >
+        <property name="alignment">
          <set>Qt::AlignRight|Qt::AlignTrailing|Qt::AlignVCenter</set>
         </property>
        </widget>
       </item>
-      <item row="1" column="2" >
-       <widget class="QLabel" name="label_6" >
-        <property name="text" >
+      <item row="1" column="2">
+       <widget class="QLabel" name="label_6">
+        <property name="text">
          <string>left</string>
         </property>
-        <property name="alignment" >
+        <property name="alignment">
          <set>Qt::AlignRight|Qt::AlignTrailing|Qt::AlignVCenter</set>
         </property>
        </widget>
       </item>
-      <item row="1" column="4" >
-       <widget class="QLabel" name="label_7" >
-        <property name="text" >
+      <item row="1" column="4">
+       <widget class="QLabel" name="label_7">
+        <property name="text">
          <string>center</string>
         </property>
-        <property name="alignment" >
+        <property name="alignment">
          <set>Qt::AlignRight|Qt::AlignTrailing|Qt::AlignVCenter</set>
         </property>
        </widget>
       </item>
-      <item row="1" column="6" >
-       <widget class="QLabel" name="label_8" >
-        <property name="text" >
+      <item row="1" column="6">
+       <widget class="QLabel" name="label_8">
+        <property name="text">
          <string>right</string>
         </property>
-        <property name="alignment" >
+        <property name="alignment">
          <set>Qt::AlignRight|Qt::AlignTrailing|Qt::AlignVCenter</set>
         </property>
        </widget>
       </item>
-      <item row="0" column="1" >
-       <spacer name="horizontalSpacer" >
-        <property name="orientation" >
+      <item row="0" column="1">
+       <spacer name="horizontalSpacer">
+        <property name="orientation">
          <enum>Qt::Horizontal</enum>
         </property>
-        <property name="sizeType" >
+        <property name="sizeType">
          <enum>QSizePolicy::Fixed</enum>
         </property>
-        <property name="sizeHint" stdset="0" >
+        <property name="sizeHint" stdset="0">
          <size>
           <width>20</width>
           <height>20</height>
@@ -156,15 +157,15 @@
         </property>
        </spacer>
       </item>
-      <item row="0" column="3" >
-       <spacer name="horizontalSpacer_4" >
-        <property name="orientation" >
+      <item row="0" column="3">
+       <spacer name="horizontalSpacer_4">
+        <property name="orientation">
          <enum>Qt::Horizontal</enum>
         </property>
-        <property name="sizeType" >
+        <property name="sizeType">
          <enum>QSizePolicy::Fixed</enum>
         </property>
-        <property name="sizeHint" stdset="0" >
+        <property name="sizeHint" stdset="0">
          <size>
           <width>20</width>
           <height>20</height>
@@ -172,15 +173,15 @@
         </property>
        </spacer>
       </item>
-      <item row="0" column="5" >
-       <spacer name="horizontalSpacer_5" >
-        <property name="orientation" >
+      <item row="0" column="5">
+       <spacer name="horizontalSpacer_5">
+        <property name="orientation">
          <enum>Qt::Horizontal</enum>
         </property>
-        <property name="sizeType" >
+        <property name="sizeType">
          <enum>QSizePolicy::Fixed</enum>
         </property>
-        <property name="sizeHint" stdset="0" >
+        <property name="sizeHint" stdset="0">
          <size>
           <width>20</width>
           <height>20</height>
@@ -192,21 +193,21 @@
     </widget>
    </item>
    <item>
-    <widget class="QGroupBox" name="groupBox_2" >
-     <property name="title" >
+    <widget class="QGroupBox" name="groupBox_2">
+     <property name="title">
       <string>Vertical alignment</string>
      </property>
-     <layout class="QGridLayout" name="gridLayout_2" >
-      <item row="0" column="0" >
-       <widget class="QRadioButton" name="v_none_rb" >
-        <property name="text" >
+     <layout class="QGridLayout" name="gridLayout_2">
+      <item row="0" column="0">
+       <widget class="QRadioButton" name="v_none_rb">
+        <property name="text">
          <string/>
         </property>
-        <property name="icon" >
-         <iconset resource="layResources.qrc" >
+        <property name="icon">
+         <iconset resource="../../lay/lay/layResources.qrc">
           <normaloff>:/align_none.png</normaloff>:/align_none.png</iconset>
         </property>
-        <property name="iconSize" >
+        <property name="iconSize">
          <size>
           <width>32</width>
           <height>32</height>
@@ -214,16 +215,16 @@
         </property>
        </widget>
       </item>
-      <item row="0" column="2" >
-       <widget class="QRadioButton" name="v_top_rb" >
-        <property name="text" >
+      <item row="0" column="2">
+       <widget class="QRadioButton" name="v_top_rb">
+        <property name="text">
          <string/>
         </property>
-        <property name="icon" >
-         <iconset resource="layResources.qrc" >
+        <property name="icon">
+         <iconset resource="../../lay/lay/layResources.qrc">
           <normaloff>:/align_top.png</normaloff>:/align_top.png</iconset>
         </property>
-        <property name="iconSize" >
+        <property name="iconSize">
          <size>
           <width>32</width>
           <height>32</height>
@@ -231,16 +232,16 @@
         </property>
        </widget>
       </item>
-      <item row="0" column="4" >
-       <widget class="QRadioButton" name="v_center_rb" >
-        <property name="text" >
+      <item row="0" column="4">
+       <widget class="QRadioButton" name="v_center_rb">
+        <property name="text">
          <string/>
         </property>
-        <property name="icon" >
-         <iconset resource="layResources.qrc" >
+        <property name="icon">
+         <iconset resource="../../lay/lay/layResources.qrc">
           <normaloff>:/align_vcenter.png</normaloff>:/align_vcenter.png</iconset>
         </property>
-        <property name="iconSize" >
+        <property name="iconSize">
          <size>
           <width>32</width>
           <height>32</height>
@@ -248,12 +249,12 @@
         </property>
        </widget>
       </item>
-      <item row="0" column="7" >
-       <spacer name="horizontalSpacer_2" >
-        <property name="orientation" >
+      <item row="0" column="7">
+       <spacer name="horizontalSpacer_2">
+        <property name="orientation">
          <enum>Qt::Horizontal</enum>
         </property>
-        <property name="sizeHint" stdset="0" >
+        <property name="sizeHint" stdset="0">
          <size>
           <width>243</width>
           <height>34</height>
@@ -261,56 +262,56 @@
         </property>
        </spacer>
       </item>
-      <item row="1" column="0" >
-       <widget class="QLabel" name="label" >
-        <property name="text" >
+      <item row="1" column="0">
+       <widget class="QLabel" name="label">
+        <property name="text">
          <string>none</string>
         </property>
-        <property name="alignment" >
+        <property name="alignment">
          <set>Qt::AlignRight|Qt::AlignTrailing|Qt::AlignVCenter</set>
         </property>
        </widget>
       </item>
-      <item row="1" column="2" >
-       <widget class="QLabel" name="label_2" >
-        <property name="text" >
+      <item row="1" column="2">
+       <widget class="QLabel" name="label_2">
+        <property name="text">
          <string>top</string>
         </property>
-        <property name="alignment" >
+        <property name="alignment">
          <set>Qt::AlignRight|Qt::AlignTrailing|Qt::AlignVCenter</set>
         </property>
        </widget>
       </item>
-      <item row="1" column="4" >
-       <widget class="QLabel" name="label_3" >
-        <property name="text" >
+      <item row="1" column="4">
+       <widget class="QLabel" name="label_3">
+        <property name="text">
          <string>center</string>
         </property>
-        <property name="alignment" >
+        <property name="alignment">
          <set>Qt::AlignRight|Qt::AlignTrailing|Qt::AlignVCenter</set>
         </property>
        </widget>
       </item>
-      <item row="1" column="6" >
-       <widget class="QLabel" name="label_4" >
-        <property name="text" >
+      <item row="1" column="6">
+       <widget class="QLabel" name="label_4">
+        <property name="text">
          <string>bottom</string>
         </property>
-        <property name="alignment" >
+        <property name="alignment">
          <set>Qt::AlignRight|Qt::AlignTrailing|Qt::AlignVCenter</set>
         </property>
        </widget>
       </item>
-      <item row="0" column="6" >
-       <widget class="QRadioButton" name="v_bottom_rb" >
-        <property name="text" >
+      <item row="0" column="6">
+       <widget class="QRadioButton" name="v_bottom_rb">
+        <property name="text">
          <string/>
         </property>
-        <property name="icon" >
-         <iconset resource="layResources.qrc" >
+        <property name="icon">
+         <iconset resource="../../lay/lay/layResources.qrc">
           <normaloff>:/align_bottom.png</normaloff>:/align_bottom.png</iconset>
         </property>
-        <property name="iconSize" >
+        <property name="iconSize">
          <size>
           <width>32</width>
           <height>32</height>
@@ -318,15 +319,15 @@
         </property>
        </widget>
       </item>
-      <item row="0" column="1" >
-       <spacer name="horizontalSpacer_6" >
-        <property name="orientation" >
+      <item row="0" column="1">
+       <spacer name="horizontalSpacer_6">
+        <property name="orientation">
          <enum>Qt::Horizontal</enum>
         </property>
-        <property name="sizeType" >
+        <property name="sizeType">
          <enum>QSizePolicy::Fixed</enum>
         </property>
-        <property name="sizeHint" stdset="0" >
+        <property name="sizeHint" stdset="0">
          <size>
           <width>20</width>
           <height>20</height>
@@ -334,15 +335,15 @@
         </property>
        </spacer>
       </item>
-      <item row="0" column="3" >
-       <spacer name="horizontalSpacer_7" >
-        <property name="orientation" >
+      <item row="0" column="3">
+       <spacer name="horizontalSpacer_7">
+        <property name="orientation">
          <enum>Qt::Horizontal</enum>
         </property>
-        <property name="sizeType" >
+        <property name="sizeType">
          <enum>QSizePolicy::Fixed</enum>
         </property>
-        <property name="sizeHint" stdset="0" >
+        <property name="sizeHint" stdset="0">
          <size>
           <width>20</width>
           <height>20</height>
@@ -350,15 +351,15 @@
         </property>
        </spacer>
       </item>
-      <item row="0" column="5" >
-       <spacer name="horizontalSpacer_8" >
-        <property name="orientation" >
+      <item row="0" column="5">
+       <spacer name="horizontalSpacer_8">
+        <property name="orientation">
          <enum>Qt::Horizontal</enum>
         </property>
-        <property name="sizeType" >
+        <property name="sizeType">
          <enum>QSizePolicy::Fixed</enum>
         </property>
-        <property name="sizeHint" stdset="0" >
+        <property name="sizeHint" stdset="0">
          <size>
           <width>20</width>
           <height>20</height>
@@ -370,21 +371,21 @@
     </widget>
    </item>
    <item>
-    <widget class="QGroupBox" name="groupBox_3" >
-     <property name="title" >
+    <widget class="QGroupBox" name="groupBox_3">
+     <property name="title">
       <string>Layers for alignment of instances</string>
      </property>
-     <layout class="QGridLayout" name="gridLayout" >
-      <item row="1" column="0" >
-       <widget class="QRadioButton" name="visible_layers_rb" >
-        <property name="text" >
+     <layout class="QGridLayout" name="gridLayout">
+      <item row="1" column="0">
+       <widget class="QRadioButton" name="visible_layers_rb">
+        <property name="text">
          <string>Use visible layers only</string>
         </property>
        </widget>
       </item>
-      <item row="0" column="0" >
-       <widget class="QRadioButton" name="all_layers_rb" >
-        <property name="text" >
+      <item row="0" column="0">
+       <widget class="QRadioButton" name="all_layers_rb">
+        <property name="text">
          <string>Use all layers</string>
         </property>
        </widget>
@@ -393,11 +394,11 @@
     </widget>
    </item>
    <item>
-    <spacer name="verticalSpacer" >
-     <property name="orientation" >
+    <spacer name="verticalSpacer">
+     <property name="orientation">
       <enum>Qt::Vertical</enum>
      </property>
-     <property name="sizeHint" stdset="0" >
+     <property name="sizeHint" stdset="0">
       <size>
        <width>488</width>
        <height>16</height>
@@ -406,11 +407,11 @@
     </spacer>
    </item>
    <item>
-    <widget class="QDialogButtonBox" name="buttonBox" >
-     <property name="orientation" >
+    <widget class="QDialogButtonBox" name="buttonBox">
+     <property name="orientation">
       <enum>Qt::Horizontal</enum>
      </property>
-     <property name="standardButtons" >
+     <property name="standardButtons">
       <set>QDialogButtonBox::Cancel|QDialogButtonBox::Ok</set>
      </property>
     </widget>
@@ -431,7 +432,7 @@
   <tabstop>buttonBox</tabstop>
  </tabstops>
  <resources>
-  <include location="layResources.qrc" />
+  <include location="../../lay/lay/layResources.qrc"/>
  </resources>
  <connections>
   <connection>
@@ -440,11 +441,11 @@
    <receiver>AlignOptionsDialog</receiver>
    <slot>accept()</slot>
    <hints>
-    <hint type="sourcelabel" >
+    <hint type="sourcelabel">
      <x>248</x>
      <y>254</y>
     </hint>
-    <hint type="destinationlabel" >
+    <hint type="destinationlabel">
      <x>157</x>
      <y>274</y>
     </hint>
@@ -456,11 +457,11 @@
    <receiver>AlignOptionsDialog</receiver>
    <slot>reject()</slot>
    <hints>
-    <hint type="sourcelabel" >
+    <hint type="sourcelabel">
      <x>316</x>
      <y>260</y>
     </hint>
-    <hint type="destinationlabel" >
+    <hint type="destinationlabel">
      <x>286</x>
      <y>274</y>
     </hint>
diff --git a/src/edt/edt/DistributeOptionsDialog.ui b/src/edt/edt/DistributeOptionsDialog.ui
new file mode 100644
index 000000000..74929ebe1
--- /dev/null
+++ b/src/edt/edt/DistributeOptionsDialog.ui
@@ -0,0 +1,715 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<ui version="4.0">
+ <class>DistributeOptionsDialog</class>
+ <widget class="QDialog" name="DistributeOptionsDialog">
+  <property name="geometry">
+   <rect>
+    <x>0</x>
+    <y>0</y>
+    <width>689</width>
+    <height>574</height>
+   </rect>
+  </property>
+  <property name="windowTitle">
+   <string>Distribution Options</string>
+  </property>
+  <layout class="QVBoxLayout" name="verticalLayout">
+   <item>
+    <widget class="QGroupBox" name="h_distribute">
+     <property name="title">
+      <string>Horizontal distribution</string>
+     </property>
+     <property name="checkable">
+      <bool>true</bool>
+     </property>
+     <layout class="QGridLayout" name="gridLayout_3">
+      <item row="1" column="0" colspan="2">
+       <widget class="QLabel" name="label_9">
+        <property name="text">
+         <string>The pitch specifies the offset at which the objects are placed relative to each other. The space is the minimum distance between the objects.</string>
+        </property>
+        <property name="wordWrap">
+         <bool>true</bool>
+        </property>
+       </widget>
+      </item>
+      <item row="0" column="0" colspan="2">
+       <widget class="QFrame" name="frame">
+        <property name="frameShape">
+         <enum>QFrame::NoFrame</enum>
+        </property>
+        <property name="frameShadow">
+         <enum>QFrame::Raised</enum>
+        </property>
+        <layout class="QHBoxLayout" name="horizontalLayout">
+         <property name="leftMargin">
+          <number>0</number>
+         </property>
+         <property name="topMargin">
+          <number>0</number>
+         </property>
+         <property name="rightMargin">
+          <number>0</number>
+         </property>
+         <property name="bottomMargin">
+          <number>0</number>
+         </property>
+         <item>
+          <widget class="QLabel" name="label_10">
+           <property name="text">
+            <string>Pitch</string>
+           </property>
+          </widget>
+         </item>
+         <item>
+          <widget class="QLineEdit" name="h_pitch">
+           <property name="sizePolicy">
+            <sizepolicy hsizetype="Fixed" vsizetype="Fixed">
+             <horstretch>0</horstretch>
+             <verstretch>0</verstretch>
+            </sizepolicy>
+           </property>
+          </widget>
+         </item>
+         <item>
+          <widget class="QLabel" name="label_12">
+           <property name="text">
+            <string>µm</string>
+           </property>
+          </widget>
+         </item>
+         <item>
+          <spacer name="horizontalSpacer_9">
+           <property name="orientation">
+            <enum>Qt::Horizontal</enum>
+           </property>
+           <property name="sizeType">
+            <enum>QSizePolicy::Fixed</enum>
+           </property>
+           <property name="sizeHint" stdset="0">
+            <size>
+             <width>20</width>
+             <height>20</height>
+            </size>
+           </property>
+          </spacer>
+         </item>
+         <item>
+          <widget class="QLabel" name="label_11">
+           <property name="text">
+            <string>Space</string>
+           </property>
+          </widget>
+         </item>
+         <item>
+          <widget class="QLineEdit" name="h_space">
+           <property name="sizePolicy">
+            <sizepolicy hsizetype="Fixed" vsizetype="Fixed">
+             <horstretch>0</horstretch>
+             <verstretch>0</verstretch>
+            </sizepolicy>
+           </property>
+          </widget>
+         </item>
+         <item>
+          <widget class="QLabel" name="label_13">
+           <property name="text">
+            <string>µm</string>
+           </property>
+          </widget>
+         </item>
+         <item>
+          <spacer name="horizontalSpacer">
+           <property name="orientation">
+            <enum>Qt::Horizontal</enum>
+           </property>
+           <property name="sizeHint" stdset="0">
+            <size>
+             <width>40</width>
+             <height>20</height>
+            </size>
+           </property>
+          </spacer>
+         </item>
+        </layout>
+       </widget>
+      </item>
+     </layout>
+    </widget>
+   </item>
+   <item>
+    <widget class="QGroupBox" name="v_distribute">
+     <property name="minimumSize">
+      <size>
+       <width>0</width>
+       <height>0</height>
+      </size>
+     </property>
+     <property name="title">
+      <string>Vertical distribution</string>
+     </property>
+     <property name="checkable">
+      <bool>true</bool>
+     </property>
+     <layout class="QGridLayout" name="gridLayout_4">
+      <item row="0" column="0">
+       <widget class="QFrame" name="frame_2">
+        <property name="frameShape">
+         <enum>QFrame::NoFrame</enum>
+        </property>
+        <property name="frameShadow">
+         <enum>QFrame::Raised</enum>
+        </property>
+        <layout class="QHBoxLayout" name="horizontalLayout_3">
+         <property name="leftMargin">
+          <number>0</number>
+         </property>
+         <property name="topMargin">
+          <number>0</number>
+         </property>
+         <property name="rightMargin">
+          <number>0</number>
+         </property>
+         <property name="bottomMargin">
+          <number>0</number>
+         </property>
+         <item>
+          <widget class="QLabel" name="label_18">
+           <property name="text">
+            <string>Pitch</string>
+           </property>
+          </widget>
+         </item>
+         <item>
+          <widget class="QLineEdit" name="v_pitch">
+           <property name="sizePolicy">
+            <sizepolicy hsizetype="Fixed" vsizetype="Fixed">
+             <horstretch>0</horstretch>
+             <verstretch>0</verstretch>
+            </sizepolicy>
+           </property>
+          </widget>
+         </item>
+         <item>
+          <widget class="QLabel" name="label_19">
+           <property name="text">
+            <string>µm</string>
+           </property>
+          </widget>
+         </item>
+         <item>
+          <spacer name="horizontalSpacer_12">
+           <property name="orientation">
+            <enum>Qt::Horizontal</enum>
+           </property>
+           <property name="sizeType">
+            <enum>QSizePolicy::Fixed</enum>
+           </property>
+           <property name="sizeHint" stdset="0">
+            <size>
+             <width>20</width>
+             <height>20</height>
+            </size>
+           </property>
+          </spacer>
+         </item>
+         <item>
+          <widget class="QLabel" name="label_20">
+           <property name="text">
+            <string>Space</string>
+           </property>
+          </widget>
+         </item>
+         <item>
+          <widget class="QLineEdit" name="v_space">
+           <property name="sizePolicy">
+            <sizepolicy hsizetype="Fixed" vsizetype="Fixed">
+             <horstretch>0</horstretch>
+             <verstretch>0</verstretch>
+            </sizepolicy>
+           </property>
+          </widget>
+         </item>
+         <item>
+          <widget class="QLabel" name="label_21">
+           <property name="text">
+            <string>µm</string>
+           </property>
+          </widget>
+         </item>
+         <item>
+          <spacer name="horizontalSpacer_13">
+           <property name="orientation">
+            <enum>Qt::Horizontal</enum>
+           </property>
+           <property name="sizeHint" stdset="0">
+            <size>
+             <width>40</width>
+             <height>20</height>
+            </size>
+           </property>
+          </spacer>
+         </item>
+        </layout>
+       </widget>
+      </item>
+      <item row="1" column="0">
+       <widget class="QLabel" name="label_22">
+        <property name="text">
+         <string>The pitch specifies the offset at which the objects are placed relative to each other. The space is the minimum distance between the objects.</string>
+        </property>
+        <property name="wordWrap">
+         <bool>true</bool>
+        </property>
+       </widget>
+      </item>
+     </layout>
+    </widget>
+   </item>
+   <item>
+    <widget class="QGroupBox" name="groupBox_4">
+     <property name="title">
+      <string>Horizonal alignment</string>
+     </property>
+     <layout class="QGridLayout" name="gridLayout_5">
+      <item row="0" column="0">
+       <widget class="QRadioButton" name="h_none_rb">
+        <property name="text">
+         <string/>
+        </property>
+        <property name="icon">
+         <iconset resource="../../lay/lay/layResources.qrc">
+          <normaloff>:/align_none.png</normaloff>:/align_none.png</iconset>
+        </property>
+        <property name="iconSize">
+         <size>
+          <width>32</width>
+          <height>32</height>
+         </size>
+        </property>
+       </widget>
+      </item>
+      <item row="0" column="1">
+       <spacer name="horizontalSpacer_14">
+        <property name="orientation">
+         <enum>Qt::Horizontal</enum>
+        </property>
+        <property name="sizeType">
+         <enum>QSizePolicy::Fixed</enum>
+        </property>
+        <property name="sizeHint" stdset="0">
+         <size>
+          <width>20</width>
+          <height>20</height>
+         </size>
+        </property>
+       </spacer>
+      </item>
+      <item row="0" column="2">
+       <widget class="QRadioButton" name="h_left_rb">
+        <property name="text">
+         <string/>
+        </property>
+        <property name="icon">
+         <iconset resource="../../lay/lay/layResources.qrc">
+          <normaloff>:/align_left.png</normaloff>:/align_left.png</iconset>
+        </property>
+        <property name="iconSize">
+         <size>
+          <width>32</width>
+          <height>32</height>
+         </size>
+        </property>
+       </widget>
+      </item>
+      <item row="0" column="3">
+       <spacer name="horizontalSpacer_4">
+        <property name="orientation">
+         <enum>Qt::Horizontal</enum>
+        </property>
+        <property name="sizeType">
+         <enum>QSizePolicy::Fixed</enum>
+        </property>
+        <property name="sizeHint" stdset="0">
+         <size>
+          <width>20</width>
+          <height>20</height>
+         </size>
+        </property>
+       </spacer>
+      </item>
+      <item row="0" column="4">
+       <widget class="QRadioButton" name="h_center_rb">
+        <property name="text">
+         <string/>
+        </property>
+        <property name="icon">
+         <iconset resource="../../lay/lay/layResources.qrc">
+          <normaloff>:/align_hcenter.png</normaloff>:/align_hcenter.png</iconset>
+        </property>
+        <property name="iconSize">
+         <size>
+          <width>32</width>
+          <height>32</height>
+         </size>
+        </property>
+       </widget>
+      </item>
+      <item row="0" column="5">
+       <spacer name="horizontalSpacer_5">
+        <property name="orientation">
+         <enum>Qt::Horizontal</enum>
+        </property>
+        <property name="sizeType">
+         <enum>QSizePolicy::Fixed</enum>
+        </property>
+        <property name="sizeHint" stdset="0">
+         <size>
+          <width>20</width>
+          <height>20</height>
+         </size>
+        </property>
+       </spacer>
+      </item>
+      <item row="0" column="6">
+       <widget class="QRadioButton" name="h_right_rb">
+        <property name="text">
+         <string/>
+        </property>
+        <property name="icon">
+         <iconset resource="../../lay/lay/layResources.qrc">
+          <normaloff>:/align_right.png</normaloff>:/align_right.png</iconset>
+        </property>
+        <property name="iconSize">
+         <size>
+          <width>32</width>
+          <height>32</height>
+         </size>
+        </property>
+       </widget>
+      </item>
+      <item row="0" column="7">
+       <spacer name="horizontalSpacer_3">
+        <property name="orientation">
+         <enum>Qt::Horizontal</enum>
+        </property>
+        <property name="sizeHint" stdset="0">
+         <size>
+          <width>245</width>
+          <height>20</height>
+         </size>
+        </property>
+       </spacer>
+      </item>
+      <item row="1" column="0">
+       <widget class="QLabel" name="label_23">
+        <property name="text">
+         <string>none</string>
+        </property>
+        <property name="alignment">
+         <set>Qt::AlignRight|Qt::AlignTrailing|Qt::AlignVCenter</set>
+        </property>
+       </widget>
+      </item>
+      <item row="1" column="2">
+       <widget class="QLabel" name="label_6">
+        <property name="text">
+         <string>left</string>
+        </property>
+        <property name="alignment">
+         <set>Qt::AlignRight|Qt::AlignTrailing|Qt::AlignVCenter</set>
+        </property>
+       </widget>
+      </item>
+      <item row="1" column="4">
+       <widget class="QLabel" name="label_7">
+        <property name="text">
+         <string>center</string>
+        </property>
+        <property name="alignment">
+         <set>Qt::AlignRight|Qt::AlignTrailing|Qt::AlignVCenter</set>
+        </property>
+       </widget>
+      </item>
+      <item row="1" column="6">
+       <widget class="QLabel" name="label_8">
+        <property name="text">
+         <string>right</string>
+        </property>
+        <property name="alignment">
+         <set>Qt::AlignRight|Qt::AlignTrailing|Qt::AlignVCenter</set>
+        </property>
+       </widget>
+      </item>
+     </layout>
+    </widget>
+   </item>
+   <item>
+    <widget class="QGroupBox" name="groupBox">
+     <property name="title">
+      <string>Vertical alignment</string>
+     </property>
+     <layout class="QGridLayout" name="gridLayout_2">
+      <item row="0" column="0">
+       <widget class="QRadioButton" name="v_none_rb">
+        <property name="text">
+         <string/>
+        </property>
+        <property name="icon">
+         <iconset resource="../../lay/lay/layResources.qrc">
+          <normaloff>:/align_none.png</normaloff>:/align_none.png</iconset>
+        </property>
+        <property name="iconSize">
+         <size>
+          <width>32</width>
+          <height>32</height>
+         </size>
+        </property>
+       </widget>
+      </item>
+      <item row="0" column="1">
+       <spacer name="horizontalSpacer_15">
+        <property name="orientation">
+         <enum>Qt::Horizontal</enum>
+        </property>
+        <property name="sizeType">
+         <enum>QSizePolicy::Fixed</enum>
+        </property>
+        <property name="sizeHint" stdset="0">
+         <size>
+          <width>20</width>
+          <height>20</height>
+         </size>
+        </property>
+       </spacer>
+      </item>
+      <item row="0" column="2">
+       <widget class="QRadioButton" name="v_top_rb">
+        <property name="text">
+         <string/>
+        </property>
+        <property name="icon">
+         <iconset resource="../../lay/lay/layResources.qrc">
+          <normaloff>:/align_top.png</normaloff>:/align_top.png</iconset>
+        </property>
+        <property name="iconSize">
+         <size>
+          <width>32</width>
+          <height>32</height>
+         </size>
+        </property>
+       </widget>
+      </item>
+      <item row="0" column="3">
+       <spacer name="horizontalSpacer_8">
+        <property name="orientation">
+         <enum>Qt::Horizontal</enum>
+        </property>
+        <property name="sizeType">
+         <enum>QSizePolicy::Fixed</enum>
+        </property>
+        <property name="sizeHint" stdset="0">
+         <size>
+          <width>20</width>
+          <height>20</height>
+         </size>
+        </property>
+       </spacer>
+      </item>
+      <item row="0" column="4">
+       <widget class="QRadioButton" name="v_center_rb">
+        <property name="text">
+         <string/>
+        </property>
+        <property name="icon">
+         <iconset resource="../../lay/lay/layResources.qrc">
+          <normaloff>:/align_vcenter.png</normaloff>:/align_vcenter.png</iconset>
+        </property>
+        <property name="iconSize">
+         <size>
+          <width>32</width>
+          <height>32</height>
+         </size>
+        </property>
+       </widget>
+      </item>
+      <item row="0" column="5">
+       <spacer name="horizontalSpacer_7">
+        <property name="orientation">
+         <enum>Qt::Horizontal</enum>
+        </property>
+        <property name="sizeType">
+         <enum>QSizePolicy::Fixed</enum>
+        </property>
+        <property name="sizeHint" stdset="0">
+         <size>
+          <width>20</width>
+          <height>20</height>
+         </size>
+        </property>
+       </spacer>
+      </item>
+      <item row="0" column="6">
+       <widget class="QRadioButton" name="v_bottom_rb">
+        <property name="text">
+         <string/>
+        </property>
+        <property name="icon">
+         <iconset resource="../../lay/lay/layResources.qrc">
+          <normaloff>:/align_bottom.png</normaloff>:/align_bottom.png</iconset>
+        </property>
+        <property name="iconSize">
+         <size>
+          <width>32</width>
+          <height>32</height>
+         </size>
+        </property>
+       </widget>
+      </item>
+      <item row="0" column="7">
+       <spacer name="horizontalSpacer_6">
+        <property name="orientation">
+         <enum>Qt::Horizontal</enum>
+        </property>
+        <property name="sizeHint" stdset="0">
+         <size>
+          <width>245</width>
+          <height>20</height>
+         </size>
+        </property>
+       </spacer>
+      </item>
+      <item row="1" column="0">
+       <widget class="QLabel" name="label_16">
+        <property name="text">
+         <string>none</string>
+        </property>
+        <property name="alignment">
+         <set>Qt::AlignRight|Qt::AlignTrailing|Qt::AlignVCenter</set>
+        </property>
+       </widget>
+      </item>
+      <item row="1" column="2">
+       <widget class="QLabel" name="label_14">
+        <property name="text">
+         <string>top</string>
+        </property>
+        <property name="alignment">
+         <set>Qt::AlignRight|Qt::AlignTrailing|Qt::AlignVCenter</set>
+        </property>
+       </widget>
+      </item>
+      <item row="1" column="4">
+       <widget class="QLabel" name="label_15">
+        <property name="text">
+         <string>center</string>
+        </property>
+        <property name="alignment">
+         <set>Qt::AlignRight|Qt::AlignTrailing|Qt::AlignVCenter</set>
+        </property>
+       </widget>
+      </item>
+      <item row="1" column="6">
+       <widget class="QLabel" name="label_17">
+        <property name="text">
+         <string>bottom</string>
+        </property>
+        <property name="alignment">
+         <set>Qt::AlignRight|Qt::AlignTrailing|Qt::AlignVCenter</set>
+        </property>
+       </widget>
+      </item>
+     </layout>
+    </widget>
+   </item>
+   <item>
+    <widget class="QGroupBox" name="groupBox_3">
+     <property name="title">
+      <string>For the computation of cell instance bounding boxes ...</string>
+     </property>
+     <layout class="QGridLayout" name="gridLayout">
+      <item row="1" column="0">
+       <widget class="QRadioButton" name="visible_layers_rb">
+        <property name="text">
+         <string>Use visible layers only</string>
+        </property>
+       </widget>
+      </item>
+      <item row="0" column="0">
+       <widget class="QRadioButton" name="all_layers_rb">
+        <property name="text">
+         <string>Use all layers</string>
+        </property>
+       </widget>
+      </item>
+     </layout>
+    </widget>
+   </item>
+   <item>
+    <spacer name="verticalSpacer">
+     <property name="orientation">
+      <enum>Qt::Vertical</enum>
+     </property>
+     <property name="sizeHint" stdset="0">
+      <size>
+       <width>488</width>
+       <height>16</height>
+      </size>
+     </property>
+    </spacer>
+   </item>
+   <item>
+    <widget class="QDialogButtonBox" name="buttonBox">
+     <property name="orientation">
+      <enum>Qt::Horizontal</enum>
+     </property>
+     <property name="standardButtons">
+      <set>QDialogButtonBox::Cancel|QDialogButtonBox::Ok</set>
+     </property>
+    </widget>
+   </item>
+  </layout>
+ </widget>
+ <tabstops>
+  <tabstop>all_layers_rb</tabstop>
+  <tabstop>visible_layers_rb</tabstop>
+  <tabstop>buttonBox</tabstop>
+ </tabstops>
+ <resources>
+  <include location="../../lay/lay/layResources.qrc"/>
+ </resources>
+ <connections>
+  <connection>
+   <sender>buttonBox</sender>
+   <signal>accepted()</signal>
+   <receiver>DistributeOptionsDialog</receiver>
+   <slot>accept()</slot>
+   <hints>
+    <hint type="sourcelabel">
+     <x>248</x>
+     <y>254</y>
+    </hint>
+    <hint type="destinationlabel">
+     <x>157</x>
+     <y>274</y>
+    </hint>
+   </hints>
+  </connection>
+  <connection>
+   <sender>buttonBox</sender>
+   <signal>rejected()</signal>
+   <receiver>DistributeOptionsDialog</receiver>
+   <slot>reject()</slot>
+   <hints>
+    <hint type="sourcelabel">
+     <x>316</x>
+     <y>260</y>
+    </hint>
+    <hint type="destinationlabel">
+     <x>286</x>
+     <y>274</y>
+    </hint>
+   </hints>
+  </connection>
+ </connections>
+</ui>
diff --git a/src/edt/edt/EditorOptionsDialog.ui b/src/edt/edt/EditorOptionsDialog.ui
deleted file mode 100644
index e34cea275..000000000
--- a/src/edt/edt/EditorOptionsDialog.ui
+++ /dev/null
@@ -1,139 +0,0 @@
-<ui version="4.0" >
- <class>EditorOptionsDialog</class>
- <widget class="QDialog" name="EditorOptionsDialog" >
-  <property name="geometry" >
-   <rect>
-    <x>0</x>
-    <y>0</y>
-    <width>642</width>
-    <height>572</height>
-   </rect>
-  </property>
-  <property name="windowTitle" >
-   <string>Object Editor Options</string>
-  </property>
-  <layout class="QVBoxLayout" >
-   <property name="margin" >
-    <number>9</number>
-   </property>
-   <property name="spacing" >
-    <number>6</number>
-   </property>
-   <item>
-    <widget class="QTabWidget" name="pages" >
-     <property name="currentIndex" >
-      <number>0</number>
-     </property>
-     <widget class="QWidget" name="tab_2" >
-      <attribute name="title" >
-       <string>Tab 2</string>
-      </attribute>
-     </widget>
-    </widget>
-   </item>
-   <item>
-    <spacer>
-     <property name="orientation" >
-      <enum>Qt::Vertical</enum>
-     </property>
-     <property name="sizeType" >
-      <enum>QSizePolicy::Fixed</enum>
-     </property>
-     <property name="sizeHint" >
-      <size>
-       <width>20</width>
-       <height>8</height>
-      </size>
-     </property>
-    </spacer>
-   </item>
-   <item>
-    <widget class="QFrame" name="frame" >
-     <property name="frameShape" >
-      <enum>QFrame::NoFrame</enum>
-     </property>
-     <property name="frameShadow" >
-      <enum>QFrame::Raised</enum>
-     </property>
-     <layout class="QHBoxLayout" >
-      <property name="margin" >
-       <number>0</number>
-      </property>
-      <property name="spacing" >
-       <number>6</number>
-      </property>
-      <item>
-       <spacer>
-        <property name="orientation" >
-         <enum>Qt::Horizontal</enum>
-        </property>
-        <property name="sizeHint" >
-         <size>
-          <width>40</width>
-          <height>20</height>
-         </size>
-        </property>
-       </spacer>
-      </item>
-      <item>
-       <widget class="QPushButton" name="ok_pb" >
-        <property name="text" >
-         <string>Ok</string>
-        </property>
-       </widget>
-      </item>
-      <item>
-       <widget class="QPushButton" name="apply_pb" >
-        <property name="text" >
-         <string>Apply</string>
-        </property>
-       </widget>
-      </item>
-      <item>
-       <widget class="QPushButton" name="cancel_pb" >
-        <property name="text" >
-         <string>Cancel</string>
-        </property>
-       </widget>
-      </item>
-     </layout>
-    </widget>
-   </item>
-  </layout>
- </widget>
- <resources/>
- <connections>
-  <connection>
-   <sender>cancel_pb</sender>
-   <signal>clicked()</signal>
-   <receiver>EditorOptionsDialog</receiver>
-   <slot>reject()</slot>
-   <hints>
-    <hint type="sourcelabel" >
-     <x>506</x>
-     <y>388</y>
-    </hint>
-    <hint type="destinationlabel" >
-     <x>276</x>
-     <y>205</y>
-    </hint>
-   </hints>
-  </connection>
-  <connection>
-   <sender>ok_pb</sender>
-   <signal>clicked()</signal>
-   <receiver>EditorOptionsDialog</receiver>
-   <slot>accept()</slot>
-   <hints>
-    <hint type="sourcelabel" >
-     <x>344</x>
-     <y>388</y>
-    </hint>
-    <hint type="destinationlabel" >
-     <x>276</x>
-     <y>205</y>
-    </hint>
-   </hints>
-  </connection>
- </connections>
-</ui>
diff --git a/src/edt/edt/EditorOptionsGeneric.ui b/src/edt/edt/EditorOptionsGeneric.ui
index 36c1aadd0..8de52d009 100644
--- a/src/edt/edt/EditorOptionsGeneric.ui
+++ b/src/edt/edt/EditorOptionsGeneric.ui
@@ -6,10 +6,16 @@
    <rect>
     <x>0</x>
     <y>0</y>
-    <width>500</width>
-    <height>417</height>
+    <width>400</width>
+    <height>446</height>
    </rect>
   </property>
+  <property name="sizePolicy">
+   <sizepolicy hsizetype="Ignored" vsizetype="Ignored">
+    <horstretch>0</horstretch>
+    <verstretch>0</verstretch>
+   </sizepolicy>
+  </property>
   <property name="windowTitle">
    <string>Form</string>
   </property>
@@ -18,387 +24,449 @@
     <number>6</number>
    </property>
    <property name="leftMargin">
-    <number>9</number>
+    <number>0</number>
    </property>
    <property name="topMargin">
-    <number>9</number>
+    <number>0</number>
    </property>
    <property name="rightMargin">
-    <number>9</number>
+    <number>0</number>
    </property>
    <property name="bottomMargin">
-    <number>9</number>
+    <number>0</number>
    </property>
    <item>
-    <widget class="QGroupBox" name="groupBox">
-     <property name="title">
-      <string>Snapping</string>
+    <widget class="QScrollArea" name="scrollArea">
+     <property name="frameShape">
+      <enum>QFrame::NoFrame</enum>
      </property>
-     <layout class="QGridLayout">
-      <property name="leftMargin">
-       <number>9</number>
+     <property name="frameShadow">
+      <enum>QFrame::Plain</enum>
+     </property>
+     <property name="widgetResizable">
+      <bool>true</bool>
+     </property>
+     <widget class="QWidget" name="scrollAreaWidgetContents">
+      <property name="geometry">
+       <rect>
+        <x>0</x>
+        <y>0</y>
+        <width>400</width>
+        <height>446</height>
+       </rect>
       </property>
-      <property name="topMargin">
-       <number>9</number>
-      </property>
-      <property name="rightMargin">
-       <number>9</number>
-      </property>
-      <property name="bottomMargin">
-       <number>9</number>
-      </property>
-      <property name="spacing">
-       <number>6</number>
-      </property>
-      <item row="0" column="4">
-       <spacer>
-        <property name="orientation">
-         <enum>Qt::Horizontal</enum>
-        </property>
-        <property name="sizeHint" stdset="0">
-         <size>
-          <width>148</width>
-          <height>16</height>
-         </size>
-        </property>
-       </spacer>
-      </item>
-      <item row="0" column="2">
-       <spacer>
-        <property name="orientation">
-         <enum>Qt::Horizontal</enum>
-        </property>
-        <property name="sizeType">
-         <enum>QSizePolicy::Fixed</enum>
-        </property>
-        <property name="sizeHint" stdset="0">
-         <size>
-          <width>16</width>
-          <height>20</height>
-         </size>
-        </property>
-       </spacer>
-      </item>
-      <item row="0" column="3">
-       <widget class="QLineEdit" name="edit_grid_le">
-        <property name="sizePolicy">
-         <sizepolicy hsizetype="Fixed" vsizetype="Fixed">
-          <horstretch>0</horstretch>
-          <verstretch>0</verstretch>
-         </sizepolicy>
-        </property>
-        <property name="toolTip">
-         <string>Enter the grid in micron. Can be anisotropic (&quot;gx,gy&quot;)</string>
-        </property>
-       </widget>
-      </item>
-      <item row="0" column="0">
-       <widget class="QLabel" name="label_5">
-        <property name="text">
-         <string>Grid</string>
-        </property>
-       </widget>
-      </item>
-      <item row="1" column="0">
-       <widget class="QLabel" name="label_6">
-        <property name="text">
-         <string>Objects   </string>
-        </property>
-       </widget>
-      </item>
-      <item row="0" column="1">
-       <widget class="QComboBox" name="grid_cb">
-        <item>
-         <property name="text">
-          <string>No grid</string>
+      <layout class="QVBoxLayout" name="verticalLayout">
+       <property name="spacing">
+        <number>2</number>
+       </property>
+       <property name="leftMargin">
+        <number>4</number>
+       </property>
+       <property name="topMargin">
+        <number>4</number>
+       </property>
+       <property name="rightMargin">
+        <number>4</number>
+       </property>
+       <property name="bottomMargin">
+        <number>4</number>
+       </property>
+       <item>
+        <widget class="QGroupBox" name="groupBox">
+         <property name="title">
+          <string>Snapping</string>
          </property>
-        </item>
-        <item>
-         <property name="text">
-          <string>Global grid</string>
+         <layout class="QGridLayout" name="_5">
+          <property name="leftMargin">
+           <number>4</number>
+          </property>
+          <property name="topMargin">
+           <number>4</number>
+          </property>
+          <property name="rightMargin">
+           <number>4</number>
+          </property>
+          <property name="bottomMargin">
+           <number>4</number>
+          </property>
+          <property name="horizontalSpacing">
+           <number>6</number>
+          </property>
+          <property name="verticalSpacing">
+           <number>2</number>
+          </property>
+          <item row="0" column="0">
+           <widget class="QLabel" name="label_5">
+            <property name="text">
+             <string>Grid</string>
+            </property>
+           </widget>
+          </item>
+          <item row="0" column="1">
+           <widget class="QComboBox" name="grid_cb">
+            <property name="sizePolicy">
+             <sizepolicy hsizetype="Fixed" vsizetype="Fixed">
+              <horstretch>1</horstretch>
+              <verstretch>0</verstretch>
+             </sizepolicy>
+            </property>
+            <property name="sizeAdjustPolicy">
+             <enum>QComboBox::AdjustToContents</enum>
+            </property>
+            <item>
+             <property name="text">
+              <string>No grid</string>
+             </property>
+            </item>
+            <item>
+             <property name="text">
+              <string>Global grid</string>
+             </property>
+            </item>
+            <item>
+             <property name="text">
+              <string>Other grid ...</string>
+             </property>
+            </item>
+           </widget>
+          </item>
+          <item row="1" column="1" colspan="3">
+           <widget class="QCheckBox" name="snap_objects_cbx">
+            <property name="text">
+             <string>Snap to other objects</string>
+            </property>
+           </widget>
+          </item>
+          <item row="1" column="0">
+           <widget class="QLabel" name="label_6">
+            <property name="text">
+             <string>Objects   </string>
+            </property>
+           </widget>
+          </item>
+          <item row="0" column="3">
+           <spacer>
+            <property name="orientation">
+             <enum>Qt::Horizontal</enum>
+            </property>
+            <property name="sizeHint" stdset="0">
+             <size>
+              <width>148</width>
+              <height>16</height>
+             </size>
+            </property>
+           </spacer>
+          </item>
+          <item row="0" column="2">
+           <widget class="QLineEdit" name="edit_grid_le">
+            <property name="sizePolicy">
+             <sizepolicy hsizetype="Fixed" vsizetype="Fixed">
+              <horstretch>0</horstretch>
+              <verstretch>0</verstretch>
+             </sizepolicy>
+            </property>
+            <property name="toolTip">
+             <string>Enter the grid in micron. Can be anisotropic (&quot;gx,gy&quot;)</string>
+            </property>
+           </widget>
+          </item>
+         </layout>
+        </widget>
+       </item>
+       <item>
+        <widget class="QGroupBox" name="groupBox_2">
+         <property name="title">
+          <string>Angle Constraints</string>
          </property>
-        </item>
-        <item>
-         <property name="text">
-          <string>Other grid ...</string>
+         <layout class="QGridLayout" name="_2">
+          <property name="leftMargin">
+           <number>4</number>
+          </property>
+          <property name="topMargin">
+           <number>4</number>
+          </property>
+          <property name="rightMargin">
+           <number>4</number>
+          </property>
+          <property name="bottomMargin">
+           <number>4</number>
+          </property>
+          <property name="horizontalSpacing">
+           <number>6</number>
+          </property>
+          <property name="verticalSpacing">
+           <number>2</number>
+          </property>
+          <item row="1" column="0">
+           <widget class="QLabel" name="label_3">
+            <property name="text">
+             <string>Movements   </string>
+            </property>
+           </widget>
+          </item>
+          <item row="1" column="1">
+           <widget class="QComboBox" name="move_angle_cb">
+            <property name="sizePolicy">
+             <sizepolicy hsizetype="Fixed" vsizetype="Fixed">
+              <horstretch>1</horstretch>
+              <verstretch>0</verstretch>
+             </sizepolicy>
+            </property>
+            <property name="sizeAdjustPolicy">
+             <enum>QComboBox::AdjustToContents</enum>
+            </property>
+            <item>
+             <property name="text">
+              <string>Any Direction</string>
+             </property>
+            </item>
+            <item>
+             <property name="text">
+              <string>Diagonal</string>
+             </property>
+            </item>
+            <item>
+             <property name="text">
+              <string>Manhattan</string>
+             </property>
+            </item>
+           </widget>
+          </item>
+          <item row="0" column="0">
+           <widget class="QLabel" name="label_2">
+            <property name="text">
+             <string>Connections   </string>
+            </property>
+           </widget>
+          </item>
+          <item row="0" column="1">
+           <widget class="QComboBox" name="conn_angle_cb">
+            <property name="sizePolicy">
+             <sizepolicy hsizetype="Fixed" vsizetype="Fixed">
+              <horstretch>1</horstretch>
+              <verstretch>0</verstretch>
+             </sizepolicy>
+            </property>
+            <property name="sizeAdjustPolicy">
+             <enum>QComboBox::AdjustToContents</enum>
+            </property>
+            <item>
+             <property name="text">
+              <string>Any Angle</string>
+             </property>
+            </item>
+            <item>
+             <property name="text">
+              <string>Diagonal</string>
+             </property>
+            </item>
+            <item>
+             <property name="text">
+              <string>Manhattan</string>
+             </property>
+            </item>
+           </widget>
+          </item>
+          <item row="1" column="2">
+           <spacer name="horizontalSpacer_2">
+            <property name="orientation">
+             <enum>Qt::Horizontal</enum>
+            </property>
+            <property name="sizeHint" stdset="0">
+             <size>
+              <width>40</width>
+              <height>20</height>
+             </size>
+            </property>
+           </spacer>
+          </item>
+         </layout>
+        </widget>
+       </item>
+       <item>
+        <widget class="QGroupBox" name="groupBox_3">
+         <property name="title">
+          <string>Hierarchical Features</string>
          </property>
-        </item>
-       </widget>
-      </item>
-      <item row="1" column="1" colspan="4">
-       <widget class="QCheckBox" name="snap_objects_cbx">
-        <property name="text">
-         <string>Snap to other objects</string>
-        </property>
-       </widget>
-      </item>
-     </layout>
+         <layout class="QGridLayout" name="_3">
+          <property name="leftMargin">
+           <number>4</number>
+          </property>
+          <property name="topMargin">
+           <number>4</number>
+          </property>
+          <property name="rightMargin">
+           <number>4</number>
+          </property>
+          <property name="bottomMargin">
+           <number>4</number>
+          </property>
+          <property name="horizontalSpacing">
+           <number>6</number>
+          </property>
+          <property name="verticalSpacing">
+           <number>2</number>
+          </property>
+          <item row="1" column="0">
+           <widget class="QLabel" name="label">
+            <property name="text">
+             <string>Copy mode</string>
+            </property>
+           </widget>
+          </item>
+          <item row="0" column="0">
+           <widget class="QLabel" name="label_4">
+            <property name="text">
+             <string>Shallow select</string>
+            </property>
+           </widget>
+          </item>
+          <item row="1" column="1" colspan="2">
+           <widget class="QComboBox" name="hier_copy_mode_cbx">
+            <property name="sizePolicy">
+             <sizepolicy hsizetype="Fixed" vsizetype="Fixed">
+              <horstretch>1</horstretch>
+              <verstretch>0</verstretch>
+             </sizepolicy>
+            </property>
+            <property name="sizeAdjustPolicy">
+             <enum>QComboBox::AdjustToContents</enum>
+            </property>
+            <item>
+             <property name="text">
+              <string>Shallow mode (instance only)</string>
+             </property>
+            </item>
+            <item>
+             <property name="text">
+              <string>Deep mode (instance and cell)</string>
+             </property>
+            </item>
+            <item>
+             <property name="text">
+              <string>Ask</string>
+             </property>
+            </item>
+           </widget>
+          </item>
+          <item row="1" column="3">
+           <spacer name="horizontalSpacer">
+            <property name="orientation">
+             <enum>Qt::Horizontal</enum>
+            </property>
+            <property name="sizeHint" stdset="0">
+             <size>
+              <width>40</width>
+              <height>20</height>
+             </size>
+            </property>
+           </spacer>
+          </item>
+          <item row="0" column="1" colspan="3">
+           <widget class="QCheckBox" name="hier_sel_cbx">
+            <property name="sizePolicy">
+             <sizepolicy hsizetype="Expanding" vsizetype="Fixed">
+              <horstretch>0</horstretch>
+              <verstretch>0</verstretch>
+             </sizepolicy>
+            </property>
+            <property name="text">
+             <string>Select top level objects only</string>
+            </property>
+           </widget>
+          </item>
+         </layout>
+        </widget>
+       </item>
+       <item>
+        <widget class="QGroupBox" name="groupBox_4">
+         <property name="title">
+          <string>Instance Display</string>
+         </property>
+         <layout class="QHBoxLayout" name="_4">
+          <property name="spacing">
+           <number>2</number>
+          </property>
+          <property name="leftMargin">
+           <number>4</number>
+          </property>
+          <property name="topMargin">
+           <number>4</number>
+          </property>
+          <property name="rightMargin">
+           <number>4</number>
+          </property>
+          <property name="bottomMargin">
+           <number>4</number>
+          </property>
+          <item>
+           <widget class="QCheckBox" name="show_shapes_cbx">
+            <property name="text">
+             <string>Show shapes while moving (max.</string>
+            </property>
+           </widget>
+          </item>
+          <item>
+           <widget class="QLineEdit" name="max_shapes_le">
+            <property name="sizePolicy">
+             <sizepolicy hsizetype="Preferred" vsizetype="Fixed">
+              <horstretch>0</horstretch>
+              <verstretch>0</verstretch>
+             </sizepolicy>
+            </property>
+           </widget>
+          </item>
+          <item>
+           <widget class="QLabel" name="label_13">
+            <property name="text">
+             <string> shapes)</string>
+            </property>
+           </widget>
+          </item>
+          <item>
+           <spacer>
+            <property name="orientation">
+             <enum>Qt::Horizontal</enum>
+            </property>
+            <property name="sizeHint" stdset="0">
+             <size>
+              <width>20</width>
+              <height>20</height>
+             </size>
+            </property>
+           </spacer>
+          </item>
+         </layout>
+        </widget>
+       </item>
+       <item>
+        <spacer name="spacer">
+         <property name="orientation">
+          <enum>Qt::Vertical</enum>
+         </property>
+         <property name="sizeHint" stdset="0">
+          <size>
+           <width>121</width>
+           <height>70</height>
+          </size>
+         </property>
+        </spacer>
+       </item>
+      </layout>
+     </widget>
     </widget>
    </item>
-   <item>
-    <widget class="QGroupBox" name="groupBox_2">
-     <property name="title">
-      <string>Angle Constraints</string>
-     </property>
-     <layout class="QGridLayout">
-      <property name="leftMargin">
-       <number>9</number>
-      </property>
-      <property name="topMargin">
-       <number>9</number>
-      </property>
-      <property name="rightMargin">
-       <number>9</number>
-      </property>
-      <property name="bottomMargin">
-       <number>9</number>
-      </property>
-      <property name="spacing">
-       <number>6</number>
-      </property>
-      <item row="1" column="0">
-       <widget class="QLabel" name="label_3">
-        <property name="text">
-         <string>Movements   </string>
-        </property>
-       </widget>
-      </item>
-      <item row="0" column="0">
-       <widget class="QLabel" name="label_2">
-        <property name="text">
-         <string>Connections   </string>
-        </property>
-       </widget>
-      </item>
-      <item row="0" column="1">
-       <widget class="QComboBox" name="conn_angle_cb">
-        <item>
-         <property name="text">
-          <string>Any Angle</string>
-         </property>
-        </item>
-        <item>
-         <property name="text">
-          <string>Diagonal</string>
-         </property>
-        </item>
-        <item>
-         <property name="text">
-          <string>Manhattan</string>
-         </property>
-        </item>
-       </widget>
-      </item>
-      <item row="1" column="1">
-       <widget class="QComboBox" name="move_angle_cb">
-        <item>
-         <property name="text">
-          <string>Any Direction</string>
-         </property>
-        </item>
-        <item>
-         <property name="text">
-          <string>Diagonal</string>
-         </property>
-        </item>
-        <item>
-         <property name="text">
-          <string>Manhattan</string>
-         </property>
-        </item>
-       </widget>
-      </item>
-      <item row="0" column="2" rowspan="2">
-       <spacer>
-        <property name="orientation">
-         <enum>Qt::Horizontal</enum>
-        </property>
-        <property name="sizeHint" stdset="0">
-         <size>
-          <width>257</width>
-          <height>41</height>
-         </size>
-        </property>
-       </spacer>
-      </item>
-     </layout>
-    </widget>
-   </item>
-   <item>
-    <widget class="QGroupBox" name="groupBox_3">
-     <property name="title">
-      <string>Hierarchical Features</string>
-     </property>
-     <layout class="QGridLayout">
-      <property name="leftMargin">
-       <number>9</number>
-      </property>
-      <property name="topMargin">
-       <number>9</number>
-      </property>
-      <property name="rightMargin">
-       <number>9</number>
-      </property>
-      <property name="bottomMargin">
-       <number>9</number>
-      </property>
-      <property name="spacing">
-       <number>6</number>
-      </property>
-      <item row="1" column="0">
-       <widget class="QLabel" name="label">
-        <property name="text">
-         <string>Copy mode</string>
-        </property>
-       </widget>
-      </item>
-      <item row="0" column="0">
-       <widget class="QLabel" name="label_4">
-        <property name="text">
-         <string>Shallow select</string>
-        </property>
-       </widget>
-      </item>
-      <item row="1" column="1" colspan="2">
-       <widget class="QComboBox" name="hier_copy_mode_cbx">
-        <property name="sizePolicy">
-         <sizepolicy hsizetype="Preferred" vsizetype="Fixed">
-          <horstretch>0</horstretch>
-          <verstretch>0</verstretch>
-         </sizepolicy>
-        </property>
-        <property name="sizeAdjustPolicy">
-         <enum>QComboBox::AdjustToContentsOnFirstShow</enum>
-        </property>
-        <item>
-         <property name="text">
-          <string>Shallow mode (instance only)</string>
-         </property>
-        </item>
-        <item>
-         <property name="text">
-          <string>Deep mode (instance and cell)</string>
-         </property>
-        </item>
-        <item>
-         <property name="text">
-          <string>Ask</string>
-         </property>
-        </item>
-       </widget>
-      </item>
-      <item row="1" column="3">
-       <spacer name="horizontalSpacer">
-        <property name="orientation">
-         <enum>Qt::Horizontal</enum>
-        </property>
-        <property name="sizeHint" stdset="0">
-         <size>
-          <width>40</width>
-          <height>20</height>
-         </size>
-        </property>
-       </spacer>
-      </item>
-      <item row="0" column="1" colspan="3">
-       <widget class="QCheckBox" name="hier_sel_cbx">
-        <property name="sizePolicy">
-         <sizepolicy hsizetype="Expanding" vsizetype="Fixed">
-          <horstretch>0</horstretch>
-          <verstretch>0</verstretch>
-         </sizepolicy>
-        </property>
-        <property name="text">
-         <string>Select top level objects only</string>
-        </property>
-       </widget>
-      </item>
-     </layout>
-    </widget>
-   </item>
-   <item>
-    <widget class="QGroupBox" name="groupBox_4">
-     <property name="title">
-      <string>Instance Display</string>
-     </property>
-     <layout class="QHBoxLayout">
-      <property name="spacing">
-       <number>6</number>
-      </property>
-      <property name="leftMargin">
-       <number>9</number>
-      </property>
-      <property name="topMargin">
-       <number>9</number>
-      </property>
-      <property name="rightMargin">
-       <number>9</number>
-      </property>
-      <property name="bottomMargin">
-       <number>9</number>
-      </property>
-      <item>
-       <widget class="QCheckBox" name="show_shapes_cbx">
-        <property name="text">
-         <string>Show shapes when moving (max.</string>
-        </property>
-       </widget>
-      </item>
-      <item>
-       <widget class="QLineEdit" name="max_shapes_le">
-        <property name="sizePolicy">
-         <sizepolicy hsizetype="Preferred" vsizetype="Fixed">
-          <horstretch>0</horstretch>
-          <verstretch>0</verstretch>
-         </sizepolicy>
-        </property>
-       </widget>
-      </item>
-      <item>
-       <widget class="QLabel" name="label_13">
-        <property name="text">
-         <string>shapes)</string>
-        </property>
-       </widget>
-      </item>
-      <item>
-       <spacer>
-        <property name="orientation">
-         <enum>Qt::Horizontal</enum>
-        </property>
-        <property name="sizeHint" stdset="0">
-         <size>
-          <width>20</width>
-          <height>20</height>
-         </size>
-        </property>
-       </spacer>
-      </item>
-     </layout>
-    </widget>
-   </item>
-   <item>
-    <spacer>
-     <property name="orientation">
-      <enum>Qt::Vertical</enum>
-     </property>
-     <property name="sizeHint" stdset="0">
-      <size>
-       <width>121</width>
-       <height>51</height>
-      </size>
-     </property>
-    </spacer>
-   </item>
   </layout>
  </widget>
  <tabstops>
+  <tabstop>scrollArea</tabstop>
   <tabstop>grid_cb</tabstop>
   <tabstop>edit_grid_le</tabstop>
   <tabstop>snap_objects_cbx</tabstop>
   <tabstop>conn_angle_cb</tabstop>
   <tabstop>move_angle_cb</tabstop>
   <tabstop>hier_sel_cbx</tabstop>
+  <tabstop>hier_copy_mode_cbx</tabstop>
   <tabstop>show_shapes_cbx</tabstop>
   <tabstop>max_shapes_le</tabstop>
  </tabstops>
diff --git a/src/edt/edt/EditorOptionsInst.ui b/src/edt/edt/EditorOptionsInst.ui
index 3cd38120a..53002f9de 100644
--- a/src/edt/edt/EditorOptionsInst.ui
+++ b/src/edt/edt/EditorOptionsInst.ui
@@ -6,10 +6,16 @@
    <rect>
     <x>0</x>
     <y>0</y>
-    <width>680</width>
-    <height>574</height>
+    <width>358</width>
+    <height>496</height>
    </rect>
   </property>
+  <property name="sizePolicy">
+   <sizepolicy hsizetype="Ignored" vsizetype="Ignored">
+    <horstretch>0</horstretch>
+    <verstretch>0</verstretch>
+   </sizepolicy>
+  </property>
   <property name="windowTitle">
    <string>Form</string>
   </property>
@@ -18,163 +24,218 @@
     <number>6</number>
    </property>
    <property name="leftMargin">
-    <number>9</number>
+    <number>0</number>
    </property>
    <property name="topMargin">
-    <number>9</number>
+    <number>0</number>
    </property>
    <property name="rightMargin">
-    <number>9</number>
+    <number>0</number>
    </property>
    <property name="bottomMargin">
-    <number>9</number>
+    <number>0</number>
    </property>
    <item>
-    <widget class="QFrame" name="frame">
+    <widget class="QScrollArea" name="scrollArea">
      <property name="frameShape">
       <enum>QFrame::NoFrame</enum>
      </property>
      <property name="frameShadow">
-      <enum>QFrame::Raised</enum>
+      <enum>QFrame::Plain</enum>
      </property>
-     <layout class="QHBoxLayout">
-      <property name="spacing">
-       <number>6</number>
+     <property name="widgetResizable">
+      <bool>true</bool>
+     </property>
+     <widget class="QWidget" name="scrollAreaWidgetContents">
+      <property name="geometry">
+       <rect>
+        <x>0</x>
+        <y>0</y>
+        <width>358</width>
+        <height>496</height>
+       </rect>
       </property>
-      <property name="leftMargin">
-       <number>0</number>
-      </property>
-      <property name="topMargin">
-       <number>0</number>
-      </property>
-      <property name="rightMargin">
-       <number>0</number>
-      </property>
-      <property name="bottomMargin">
-       <number>0</number>
-      </property>
-      <item>
-       <widget class="QLabel" name="label_2">
-        <property name="sizePolicy">
-         <sizepolicy hsizetype="Fixed" vsizetype="Fixed">
-          <horstretch>0</horstretch>
-          <verstretch>0</verstretch>
-         </sizepolicy>
-        </property>
-        <property name="text">
-         <string>Cell  </string>
-        </property>
-       </widget>
-      </item>
-      <item>
-       <widget class="QLineEdit" name="cell_le">
-        <property name="sizePolicy">
-         <sizepolicy hsizetype="Expanding" vsizetype="Fixed">
-          <horstretch>0</horstretch>
-          <verstretch>0</verstretch>
-         </sizepolicy>
-        </property>
-       </widget>
-      </item>
-      <item>
-       <widget class="QToolButton" name="browse_pb">
-        <property name="text">
-         <string>...</string>
-        </property>
-       </widget>
-      </item>
-      <item>
-       <widget class="QLabel" name="label_13">
-        <property name="text">
-         <string>  Library  </string>
-        </property>
-       </widget>
-      </item>
-      <item>
-       <widget class="lay::LibrarySelectionComboBox" name="lib_cbx">
-        <property name="sizePolicy">
-         <sizepolicy hsizetype="Expanding" vsizetype="Fixed">
-          <horstretch>0</horstretch>
-          <verstretch>0</verstretch>
-         </sizepolicy>
-        </property>
-       </widget>
-      </item>
-     </layout>
-    </widget>
-   </item>
-   <item>
-    <spacer>
-     <property name="orientation">
-      <enum>Qt::Vertical</enum>
-     </property>
-     <property name="sizeType">
-      <enum>QSizePolicy::Fixed</enum>
-     </property>
-     <property name="sizeHint" stdset="0">
-      <size>
-       <width>522</width>
-       <height>8</height>
-      </size>
-     </property>
-    </spacer>
-   </item>
-   <item>
-    <widget class="QTabWidget" name="param_tab_widget">
-     <property name="sizePolicy">
-      <sizepolicy hsizetype="Expanding" vsizetype="Expanding">
-       <horstretch>0</horstretch>
-       <verstretch>1</verstretch>
-      </sizepolicy>
-     </property>
-     <property name="currentIndex">
-      <number>0</number>
-     </property>
-     <widget class="QWidget" name="tab">
-      <attribute name="title">
-       <string>Geometry</string>
-      </attribute>
-      <layout class="QVBoxLayout">
-       <property name="spacing">
-        <number>6</number>
-       </property>
+      <layout class="QGridLayout" name="gridLayout_2">
        <property name="leftMargin">
-        <number>9</number>
+        <number>4</number>
        </property>
        <property name="topMargin">
-        <number>9</number>
+        <number>4</number>
        </property>
        <property name="rightMargin">
-        <number>9</number>
+        <number>4</number>
        </property>
        <property name="bottomMargin">
-        <number>9</number>
+        <number>4</number>
        </property>
-       <item>
+       <property name="spacing">
+        <number>2</number>
+       </property>
+       <item row="0" column="0">
+        <widget class="QFrame" name="frame">
+         <property name="frameShape">
+          <enum>QFrame::NoFrame</enum>
+         </property>
+         <property name="frameShadow">
+          <enum>QFrame::Raised</enum>
+         </property>
+         <layout class="QGridLayout" name="gridLayout">
+          <property name="leftMargin">
+           <number>0</number>
+          </property>
+          <property name="topMargin">
+           <number>0</number>
+          </property>
+          <property name="rightMargin">
+           <number>0</number>
+          </property>
+          <property name="bottomMargin">
+           <number>0</number>
+          </property>
+          <property name="horizontalSpacing">
+           <number>6</number>
+          </property>
+          <property name="verticalSpacing">
+           <number>2</number>
+          </property>
+          <item row="0" column="0">
+           <widget class="QLabel" name="label_13">
+            <property name="text">
+             <string>Library</string>
+            </property>
+           </widget>
+          </item>
+          <item row="0" column="1" colspan="2">
+           <widget class="lay::LibrarySelectionComboBox" name="lib_cbx">
+            <property name="sizePolicy">
+             <sizepolicy hsizetype="Preferred" vsizetype="Fixed">
+              <horstretch>0</horstretch>
+              <verstretch>0</verstretch>
+             </sizepolicy>
+            </property>
+           </widget>
+          </item>
+          <item row="1" column="0">
+           <widget class="QLabel" name="label_2">
+            <property name="sizePolicy">
+             <sizepolicy hsizetype="Fixed" vsizetype="Fixed">
+              <horstretch>0</horstretch>
+              <verstretch>0</verstretch>
+             </sizepolicy>
+            </property>
+            <property name="text">
+             <string>Cell  </string>
+            </property>
+           </widget>
+          </item>
+          <item row="1" column="1" colspan="2">
+           <widget class="QFrame" name="frame_2">
+            <property name="frameShape">
+             <enum>QFrame::NoFrame</enum>
+            </property>
+            <property name="frameShadow">
+             <enum>QFrame::Raised</enum>
+            </property>
+            <layout class="QHBoxLayout" name="horizontalLayout">
+             <property name="spacing">
+              <number>2</number>
+             </property>
+             <property name="leftMargin">
+              <number>0</number>
+             </property>
+             <property name="topMargin">
+              <number>0</number>
+             </property>
+             <property name="rightMargin">
+              <number>0</number>
+             </property>
+             <property name="bottomMargin">
+              <number>0</number>
+             </property>
+             <item>
+              <widget class="QToolButton" name="browse_pb">
+               <property name="text">
+                <string>...</string>
+               </property>
+               <property name="icon">
+                <iconset resource="../../lay/lay/layResources.qrc">
+                 <normaloff>:/find.png</normaloff>:/find.png</iconset>
+               </property>
+               <property name="autoRaise">
+                <bool>true</bool>
+               </property>
+              </widget>
+             </item>
+             <item>
+              <widget class="QLineEdit" name="cell_le">
+               <property name="sizePolicy">
+                <sizepolicy hsizetype="Preferred" vsizetype="Fixed">
+                 <horstretch>0</horstretch>
+                 <verstretch>0</verstretch>
+                </sizepolicy>
+               </property>
+               <property name="clearButtonEnabled">
+                <bool>false</bool>
+               </property>
+              </widget>
+             </item>
+            </layout>
+           </widget>
+          </item>
+         </layout>
+        </widget>
+       </item>
+       <item row="1" column="0">
+        <spacer name="spacer">
+         <property name="orientation">
+          <enum>Qt::Vertical</enum>
+         </property>
+         <property name="sizeType">
+          <enum>QSizePolicy::Fixed</enum>
+         </property>
+         <property name="sizeHint" stdset="0">
+          <size>
+           <width>20</width>
+           <height>4</height>
+          </size>
+         </property>
+        </spacer>
+       </item>
+       <item row="2" column="0">
+        <widget class="QCheckBox" name="place_origin_cb">
+         <property name="text">
+          <string>Place origin of cell</string>
+         </property>
+        </widget>
+       </item>
+       <item row="4" column="0">
         <widget class="QGroupBox" name="groupBox">
          <property name="title">
           <string>Rotation / Scaling</string>
          </property>
-         <layout class="QGridLayout">
+         <layout class="QGridLayout" name="_2">
           <property name="leftMargin">
-           <number>9</number>
+           <number>4</number>
           </property>
           <property name="topMargin">
-           <number>9</number>
+           <number>4</number>
           </property>
           <property name="rightMargin">
-           <number>9</number>
+           <number>4</number>
           </property>
           <property name="bottomMargin">
-           <number>9</number>
+           <number>4</number>
           </property>
-          <property name="spacing">
+          <property name="horizontalSpacing">
            <number>6</number>
           </property>
+          <property name="verticalSpacing">
+           <number>2</number>
+          </property>
           <item row="0" column="1">
            <widget class="QLineEdit" name="scale_le">
             <property name="sizePolicy">
-             <sizepolicy hsizetype="Fixed" vsizetype="Fixed">
+             <sizepolicy hsizetype="Preferred" vsizetype="Fixed">
               <horstretch>0</horstretch>
               <verstretch>0</verstretch>
              </sizepolicy>
@@ -194,14 +255,14 @@
           <item row="0" column="0">
            <widget class="QLabel" name="label">
             <property name="text">
-             <string>Scaling factor (magnification)</string>
+             <string>Scaling factor</string>
             </property>
            </widget>
           </item>
           <item row="1" column="1">
            <widget class="QLineEdit" name="angle_le">
             <property name="sizePolicy">
-             <sizepolicy hsizetype="Fixed" vsizetype="Fixed">
+             <sizepolicy hsizetype="Preferred" vsizetype="Fixed">
               <horstretch>0</horstretch>
               <verstretch>0</verstretch>
              </sizepolicy>
@@ -229,10 +290,17 @@
             </property>
            </widget>
           </item>
+          <item row="0" column="2">
+           <widget class="QLabel" name="label_17">
+            <property name="text">
+             <string>(magnification)</string>
+            </property>
+           </widget>
+          </item>
          </layout>
         </widget>
        </item>
-       <item>
+       <item row="5" column="0">
         <widget class="QGroupBox" name="array_grp">
          <property name="sizePolicy">
           <sizepolicy hsizetype="Preferred" vsizetype="Preferred">
@@ -246,33 +314,36 @@
          <property name="checkable">
           <bool>true</bool>
          </property>
-         <layout class="QGridLayout">
+         <layout class="QGridLayout" name="_3">
           <property name="leftMargin">
-           <number>9</number>
+           <number>4</number>
           </property>
           <property name="topMargin">
-           <number>9</number>
+           <number>4</number>
           </property>
           <property name="rightMargin">
-           <number>9</number>
+           <number>4</number>
           </property>
           <property name="bottomMargin">
-           <number>9</number>
+           <number>4</number>
           </property>
-          <property name="spacing">
+          <property name="horizontalSpacing">
            <number>6</number>
           </property>
+          <property name="verticalSpacing">
+           <number>2</number>
+          </property>
           <item row="2" column="0">
            <widget class="QLabel" name="label_16">
             <property name="text">
-             <string>  Column vector (x,y)</string>
+             <string>  Column step</string>
             </property>
            </widget>
           </item>
           <item row="2" column="2">
            <widget class="QLineEdit" name="column_x_le">
             <property name="sizePolicy">
-             <sizepolicy hsizetype="Fixed" vsizetype="Fixed">
+             <sizepolicy hsizetype="Preferred" vsizetype="Fixed">
               <horstretch>1</horstretch>
               <verstretch>0</verstretch>
              </sizepolicy>
@@ -292,7 +363,7 @@
           <item row="2" column="4">
            <widget class="QLineEdit" name="column_y_le">
             <property name="sizePolicy">
-             <sizepolicy hsizetype="Fixed" vsizetype="Fixed">
+             <sizepolicy hsizetype="Preferred" vsizetype="Fixed">
               <horstretch>1</horstretch>
               <verstretch>0</verstretch>
              </sizepolicy>
@@ -312,7 +383,7 @@
           <item row="1" column="4">
            <widget class="QLineEdit" name="row_y_le">
             <property name="sizePolicy">
-             <sizepolicy hsizetype="Fixed" vsizetype="Fixed">
+             <sizepolicy hsizetype="Preferred" vsizetype="Fixed">
               <horstretch>1</horstretch>
               <verstretch>0</verstretch>
              </sizepolicy>
@@ -332,7 +403,7 @@
           <item row="1" column="2">
            <widget class="QLineEdit" name="row_x_le">
             <property name="sizePolicy">
-             <sizepolicy hsizetype="Fixed" vsizetype="Fixed">
+             <sizepolicy hsizetype="Preferred" vsizetype="Fixed">
               <horstretch>1</horstretch>
               <verstretch>0</verstretch>
              </sizepolicy>
@@ -352,14 +423,14 @@
           <item row="1" column="0">
            <widget class="QLabel" name="label_9">
             <property name="text">
-             <string>  Row vector (x,y)</string>
+             <string>  Row step</string>
             </property>
            </widget>
           </item>
           <item row="0" column="0">
            <widget class="QLabel" name="label_4">
             <property name="text">
-             <string>  Rows/Columns</string>
+             <string>Dimension</string>
             </property>
            </widget>
           </item>
@@ -368,12 +439,15 @@
             <property name="text">
              <string>columns =</string>
             </property>
+            <property name="alignment">
+             <set>Qt::AlignRight|Qt::AlignTrailing|Qt::AlignVCenter</set>
+            </property>
            </widget>
           </item>
           <item row="0" column="4">
            <widget class="QLineEdit" name="columns_le">
             <property name="sizePolicy">
-             <sizepolicy hsizetype="Fixed" vsizetype="Fixed">
+             <sizepolicy hsizetype="Preferred" vsizetype="Fixed">
               <horstretch>1</horstretch>
               <verstretch>0</verstretch>
              </sizepolicy>
@@ -385,74 +459,89 @@
             <property name="text">
              <string>rows = </string>
             </property>
+            <property name="alignment">
+             <set>Qt::AlignRight|Qt::AlignTrailing|Qt::AlignVCenter</set>
+            </property>
            </widget>
           </item>
           <item row="0" column="2">
            <widget class="QLineEdit" name="rows_le">
             <property name="sizePolicy">
-             <sizepolicy hsizetype="Fixed" vsizetype="Fixed">
+             <sizepolicy hsizetype="Preferred" vsizetype="Fixed">
               <horstretch>1</horstretch>
               <verstretch>0</verstretch>
              </sizepolicy>
             </property>
+            <property name="minimumSize">
+             <size>
+              <width>0</width>
+              <height>0</height>
+             </size>
+            </property>
            </widget>
           </item>
-          <item row="3" column="0" colspan="5">
+          <item row="4" column="0" colspan="5">
            <widget class="QLabel" name="label_12">
             <property name="text">
-             <string>Warning: although row and column vectors can be arbitrary combination,
-some design systems only accept orthogonal (rectangular) arrays.</string>
+             <string>Warning: although row and column vectors can be arbitrary combination, some design systems only accept orthogonal (rectangular) arrays.</string>
             </property>
             <property name="wordWrap">
              <bool>true</bool>
             </property>
            </widget>
           </item>
+          <item row="3" column="0">
+           <spacer name="verticalSpacer_2">
+            <property name="orientation">
+             <enum>Qt::Vertical</enum>
+            </property>
+            <property name="sizeType">
+             <enum>QSizePolicy::Fixed</enum>
+            </property>
+            <property name="sizeHint" stdset="0">
+             <size>
+              <width>20</width>
+              <height>4</height>
+             </size>
+            </property>
+           </spacer>
+          </item>
          </layout>
         </widget>
        </item>
-       <item>
-        <spacer>
+       <item row="6" column="0">
+        <spacer name="spacer_2">
          <property name="orientation">
           <enum>Qt::Vertical</enum>
          </property>
          <property name="sizeHint" stdset="0">
           <size>
            <width>20</width>
-           <height>40</height>
+           <height>120</height>
+          </size>
+         </property>
+        </spacer>
+       </item>
+       <item row="3" column="0">
+        <spacer name="verticalSpacer">
+         <property name="orientation">
+          <enum>Qt::Vertical</enum>
+         </property>
+         <property name="sizeType">
+          <enum>QSizePolicy::Fixed</enum>
+         </property>
+         <property name="sizeHint" stdset="0">
+          <size>
+           <width>20</width>
+           <height>4</height>
           </size>
          </property>
         </spacer>
        </item>
       </layout>
      </widget>
-     <widget class="QWidget" name="pcell_tab">
-      <attribute name="title">
-       <string>PCell</string>
-      </attribute>
-     </widget>
     </widget>
    </item>
-   <item>
-    <widget class="QCheckBox" name="place_origin_cb">
-     <property name="text">
-      <string>Place origin of cell</string>
-     </property>
-    </widget>
-   </item>
-   <item>
-    <spacer>
-     <property name="orientation">
-      <enum>Qt::Vertical</enum>
-     </property>
-     <property name="sizeHint" stdset="0">
-      <size>
-       <width>50</width>
-       <height>8</height>
-      </size>
-     </property>
-    </spacer>
-   </item>
   </layout>
  </widget>
  <customwidgets>
@@ -462,22 +551,8 @@ some design systems only accept orthogonal (rectangular) arrays.</string>
    <header>layWidgets.h</header>
   </customwidget>
  </customwidgets>
- <tabstops>
-  <tabstop>cell_le</tabstop>
-  <tabstop>browse_pb</tabstop>
-  <tabstop>lib_cbx</tabstop>
-  <tabstop>param_tab_widget</tabstop>
-  <tabstop>scale_le</tabstop>
-  <tabstop>angle_le</tabstop>
-  <tabstop>mirror_cbx</tabstop>
-  <tabstop>rows_le</tabstop>
-  <tabstop>columns_le</tabstop>
-  <tabstop>row_x_le</tabstop>
-  <tabstop>row_y_le</tabstop>
-  <tabstop>column_x_le</tabstop>
-  <tabstop>column_y_le</tabstop>
-  <tabstop>place_origin_cb</tabstop>
- </tabstops>
- <resources/>
+ <resources>
+  <include location="../../lay/lay/layResources.qrc"/>
+ </resources>
  <connections/>
 </ui>
diff --git a/src/edt/edt/EditorOptionsInstPCellParam.ui b/src/edt/edt/EditorOptionsInstPCellParam.ui
new file mode 100644
index 000000000..2e1e0178e
--- /dev/null
+++ b/src/edt/edt/EditorOptionsInstPCellParam.ui
@@ -0,0 +1,39 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<ui version="4.0">
+ <class>EditorOptionsInstPCellParam</class>
+ <widget class="QWidget" name="EditorOptionsInstPCellParam">
+  <property name="geometry">
+   <rect>
+    <x>0</x>
+    <y>0</y>
+    <width>358</width>
+    <height>481</height>
+   </rect>
+  </property>
+  <property name="sizePolicy">
+   <sizepolicy hsizetype="Ignored" vsizetype="Ignored">
+    <horstretch>0</horstretch>
+    <verstretch>0</verstretch>
+   </sizepolicy>
+  </property>
+  <property name="windowTitle">
+   <string>Form</string>
+  </property>
+  <layout class="QVBoxLayout" name="verticalLayout">
+   <property name="leftMargin">
+    <number>0</number>
+   </property>
+   <property name="topMargin">
+    <number>0</number>
+   </property>
+   <property name="rightMargin">
+    <number>0</number>
+   </property>
+   <property name="bottomMargin">
+    <number>0</number>
+   </property>
+  </layout>
+ </widget>
+ <resources/>
+ <connections/>
+</ui>
diff --git a/src/edt/edt/EditorOptionsPath.ui b/src/edt/edt/EditorOptionsPath.ui
index 543354380..c50521d5a 100644
--- a/src/edt/edt/EditorOptionsPath.ui
+++ b/src/edt/edt/EditorOptionsPath.ui
@@ -1,7 +1,8 @@
-<ui version="4.0" >
+<?xml version="1.0" encoding="UTF-8"?>
+<ui version="4.0">
  <class>EditorOptionsPath</class>
- <widget class="QWidget" name="EditorOptionsPath" >
-  <property name="geometry" >
+ <widget class="QWidget" name="EditorOptionsPath">
+  <property name="geometry">
    <rect>
     <x>0</x>
     <y>0</y>
@@ -9,228 +10,264 @@
     <height>289</height>
    </rect>
   </property>
-  <property name="windowTitle" >
+  <property name="windowTitle">
    <string>Form</string>
   </property>
-  <layout class="QVBoxLayout" >
-   <property name="margin" >
-    <number>9</number>
-   </property>
-   <property name="spacing" >
+  <layout class="QVBoxLayout">
+   <property name="spacing">
     <number>6</number>
    </property>
+   <property name="leftMargin">
+    <number>0</number>
+   </property>
+   <property name="topMargin">
+    <number>0</number>
+   </property>
+   <property name="rightMargin">
+    <number>0</number>
+   </property>
+   <property name="bottomMargin">
+    <number>0</number>
+   </property>
    <item>
-    <widget class="QFrame" name="frame_2" >
-     <property name="frameShape" >
+    <widget class="QScrollArea" name="scrollArea">
+     <property name="frameShape">
       <enum>QFrame::NoFrame</enum>
      </property>
-     <property name="frameShadow" >
-      <enum>QFrame::Raised</enum>
+     <property name="widgetResizable">
+      <bool>true</bool>
      </property>
-     <layout class="QHBoxLayout" >
-      <property name="margin" >
-       <number>0</number>
+     <widget class="QWidget" name="scrollAreaWidgetContents">
+      <property name="geometry">
+       <rect>
+        <x>0</x>
+        <y>0</y>
+        <width>357</width>
+        <height>289</height>
+       </rect>
       </property>
-      <property name="spacing" >
-       <number>6</number>
-      </property>
-      <item>
-       <widget class="QLabel" name="label_2" >
-        <property name="text" >
-         <string>  Width       </string>
-        </property>
-       </widget>
-      </item>
-      <item>
-       <widget class="QLineEdit" name="width_le" >
-        <property name="sizePolicy" >
-         <sizepolicy>
-          <hsizetype>0</hsizetype>
-          <vsizetype>0</vsizetype>
-          <horstretch>0</horstretch>
-          <verstretch>0</verstretch>
-         </sizepolicy>
-        </property>
-       </widget>
-      </item>
-      <item>
-       <widget class="QLabel" name="label_3" >
-        <property name="text" >
-         <string>micron</string>
-        </property>
-       </widget>
-      </item>
-      <item>
-       <spacer>
-        <property name="orientation" >
-         <enum>Qt::Horizontal</enum>
-        </property>
-        <property name="sizeHint" >
-         <size>
-          <width>21</width>
-          <height>20</height>
-         </size>
-        </property>
-       </spacer>
-      </item>
-     </layout>
+      <layout class="QGridLayout" name="gridLayout">
+       <item row="0" column="0">
+        <widget class="QFrame" name="frame_2">
+         <property name="frameShape">
+          <enum>QFrame::NoFrame</enum>
+         </property>
+         <property name="frameShadow">
+          <enum>QFrame::Raised</enum>
+         </property>
+         <layout class="QHBoxLayout" name="_2">
+          <property name="spacing">
+           <number>6</number>
+          </property>
+          <property name="leftMargin">
+           <number>0</number>
+          </property>
+          <property name="topMargin">
+           <number>0</number>
+          </property>
+          <property name="rightMargin">
+           <number>0</number>
+          </property>
+          <property name="bottomMargin">
+           <number>0</number>
+          </property>
+          <item>
+           <widget class="QLabel" name="label_2">
+            <property name="text">
+             <string>Width</string>
+            </property>
+           </widget>
+          </item>
+          <item>
+           <widget class="QLineEdit" name="width_le">
+            <property name="sizePolicy">
+             <sizepolicy hsizetype="Fixed" vsizetype="Fixed">
+              <horstretch>0</horstretch>
+              <verstretch>0</verstretch>
+             </sizepolicy>
+            </property>
+           </widget>
+          </item>
+          <item>
+           <widget class="QLabel" name="label_3">
+            <property name="text">
+             <string>µm</string>
+            </property>
+           </widget>
+          </item>
+          <item>
+           <spacer>
+            <property name="orientation">
+             <enum>Qt::Horizontal</enum>
+            </property>
+            <property name="sizeHint" stdset="0">
+             <size>
+              <width>21</width>
+              <height>20</height>
+             </size>
+            </property>
+           </spacer>
+          </item>
+         </layout>
+        </widget>
+       </item>
+       <item row="1" column="0">
+        <widget class="QGroupBox" name="groupBox">
+         <property name="sizePolicy">
+          <sizepolicy hsizetype="Preferred" vsizetype="Fixed">
+           <horstretch>0</horstretch>
+           <verstretch>0</verstretch>
+          </sizepolicy>
+         </property>
+         <property name="title">
+          <string>Extensions</string>
+         </property>
+         <layout class="QGridLayout" name="_3">
+          <property name="leftMargin">
+           <number>4</number>
+          </property>
+          <property name="topMargin">
+           <number>4</number>
+          </property>
+          <property name="rightMargin">
+           <number>4</number>
+          </property>
+          <property name="bottomMargin">
+           <number>4</number>
+          </property>
+          <property name="horizontalSpacing">
+           <number>6</number>
+          </property>
+          <property name="verticalSpacing">
+           <number>2</number>
+          </property>
+          <item row="2" column="1">
+           <widget class="QLabel" name="label_8">
+            <property name="text">
+             <string> end =</string>
+            </property>
+           </widget>
+          </item>
+          <item row="1" column="2">
+           <widget class="QLineEdit" name="start_ext_le">
+            <property name="sizePolicy">
+             <sizepolicy hsizetype="Fixed" vsizetype="Fixed">
+              <horstretch>1</horstretch>
+              <verstretch>0</verstretch>
+             </sizepolicy>
+            </property>
+           </widget>
+          </item>
+          <item row="2" column="3">
+           <widget class="QLabel" name="label_5">
+            <property name="text">
+             <string>µm</string>
+            </property>
+           </widget>
+          </item>
+          <item row="2" column="2">
+           <widget class="QLineEdit" name="end_ext_le">
+            <property name="sizePolicy">
+             <sizepolicy hsizetype="Fixed" vsizetype="Fixed">
+              <horstretch>1</horstretch>
+              <verstretch>0</verstretch>
+             </sizepolicy>
+            </property>
+           </widget>
+          </item>
+          <item row="0" column="1" colspan="3">
+           <widget class="QComboBox" name="type_cb">
+            <property name="sizePolicy">
+             <sizepolicy hsizetype="Fixed" vsizetype="Fixed">
+              <horstretch>0</horstretch>
+              <verstretch>0</verstretch>
+             </sizepolicy>
+            </property>
+            <item>
+             <property name="text">
+              <string>Flush</string>
+             </property>
+            </item>
+            <item>
+             <property name="text">
+              <string>Square</string>
+             </property>
+            </item>
+            <item>
+             <property name="text">
+              <string>Variable</string>
+             </property>
+            </item>
+            <item>
+             <property name="text">
+              <string>Round</string>
+             </property>
+            </item>
+           </widget>
+          </item>
+          <item row="1" column="0">
+           <widget class="QLabel" name="label_7">
+            <property name="text">
+             <string>Variable   </string>
+            </property>
+           </widget>
+          </item>
+          <item row="1" column="3">
+           <widget class="QLabel" name="label_4">
+            <property name="text">
+             <string>µm</string>
+            </property>
+           </widget>
+          </item>
+          <item row="1" column="1">
+           <widget class="QLabel" name="label_6">
+            <property name="text">
+             <string>start =</string>
+            </property>
+           </widget>
+          </item>
+          <item row="0" column="0">
+           <widget class="QLabel" name="label">
+            <property name="text">
+             <string>Type</string>
+            </property>
+           </widget>
+          </item>
+          <item row="1" column="4">
+           <spacer name="horizontalSpacer">
+            <property name="orientation">
+             <enum>Qt::Horizontal</enum>
+            </property>
+            <property name="sizeHint" stdset="0">
+             <size>
+              <width>40</width>
+              <height>20</height>
+             </size>
+            </property>
+           </spacer>
+          </item>
+         </layout>
+        </widget>
+       </item>
+       <item row="2" column="0">
+        <spacer name="spacer">
+         <property name="orientation">
+          <enum>Qt::Vertical</enum>
+         </property>
+         <property name="sizeHint" stdset="0">
+          <size>
+           <width>271</width>
+           <height>123</height>
+          </size>
+         </property>
+        </spacer>
+       </item>
+      </layout>
+     </widget>
     </widget>
    </item>
-   <item>
-    <widget class="QGroupBox" name="groupBox" >
-     <property name="sizePolicy" >
-      <sizepolicy>
-       <hsizetype>5</hsizetype>
-       <vsizetype>0</vsizetype>
-       <horstretch>0</horstretch>
-       <verstretch>0</verstretch>
-      </sizepolicy>
-     </property>
-     <property name="title" >
-      <string>Extensions</string>
-     </property>
-     <layout class="QGridLayout" >
-      <property name="margin" >
-       <number>9</number>
-      </property>
-      <property name="spacing" >
-       <number>6</number>
-      </property>
-      <item rowspan="3" row="0" column="4" >
-       <spacer>
-        <property name="orientation" >
-         <enum>Qt::Horizontal</enum>
-        </property>
-        <property name="sizeHint" >
-         <size>
-          <width>21</width>
-          <height>81</height>
-         </size>
-        </property>
-       </spacer>
-      </item>
-      <item row="2" column="3" >
-       <widget class="QLabel" name="label_5" >
-        <property name="text" >
-         <string>micron</string>
-        </property>
-       </widget>
-      </item>
-      <item row="1" column="3" >
-       <widget class="QLabel" name="label_4" >
-        <property name="text" >
-         <string>micron</string>
-        </property>
-       </widget>
-      </item>
-      <item row="2" column="2" >
-       <widget class="QLineEdit" name="end_ext_le" >
-        <property name="sizePolicy" >
-         <sizepolicy>
-          <hsizetype>0</hsizetype>
-          <vsizetype>0</vsizetype>
-          <horstretch>1</horstretch>
-          <verstretch>0</verstretch>
-         </sizepolicy>
-        </property>
-       </widget>
-      </item>
-      <item row="2" column="1" >
-       <widget class="QLabel" name="label_8" >
-        <property name="text" >
-         <string> end =</string>
-        </property>
-       </widget>
-      </item>
-      <item row="1" column="1" >
-       <widget class="QLabel" name="label_6" >
-        <property name="text" >
-         <string>start =</string>
-        </property>
-       </widget>
-      </item>
-      <item row="1" column="2" >
-       <widget class="QLineEdit" name="start_ext_le" >
-        <property name="sizePolicy" >
-         <sizepolicy>
-          <hsizetype>0</hsizetype>
-          <vsizetype>0</vsizetype>
-          <horstretch>1</horstretch>
-          <verstretch>0</verstretch>
-         </sizepolicy>
-        </property>
-       </widget>
-      </item>
-      <item row="1" column="0" >
-       <widget class="QLabel" name="label_7" >
-        <property name="text" >
-         <string>Variable   </string>
-        </property>
-       </widget>
-      </item>
-      <item row="0" column="1" colspan="2" >
-       <widget class="QComboBox" name="type_cb" >
-        <property name="sizePolicy" >
-         <sizepolicy>
-          <hsizetype>5</hsizetype>
-          <vsizetype>0</vsizetype>
-          <horstretch>0</horstretch>
-          <verstretch>0</verstretch>
-         </sizepolicy>
-        </property>
-        <item>
-         <property name="text" >
-          <string>Flush</string>
-         </property>
-        </item>
-        <item>
-         <property name="text" >
-          <string>Square</string>
-         </property>
-        </item>
-        <item>
-         <property name="text" >
-          <string>Variable</string>
-         </property>
-        </item>
-        <item>
-         <property name="text" >
-          <string>Round</string>
-         </property>
-        </item>
-       </widget>
-      </item>
-      <item row="0" column="0" >
-       <widget class="QLabel" name="label" >
-        <property name="text" >
-         <string>Type</string>
-        </property>
-       </widget>
-      </item>
-     </layout>
-    </widget>
-   </item>
-   <item>
-    <spacer>
-     <property name="orientation" >
-      <enum>Qt::Vertical</enum>
-     </property>
-     <property name="sizeHint" >
-      <size>
-       <width>271</width>
-       <height>63</height>
-      </size>
-     </property>
-    </spacer>
-   </item>
   </layout>
  </widget>
- <tabstops>
-  <tabstop>width_le</tabstop>
-  <tabstop>type_cb</tabstop>
-  <tabstop>start_ext_le</tabstop>
-  <tabstop>end_ext_le</tabstop>
- </tabstops>
  <resources/>
  <connections/>
 </ui>
diff --git a/src/edt/edt/EditorOptionsText.ui b/src/edt/edt/EditorOptionsText.ui
index 3008d9de8..1cc821fd4 100644
--- a/src/edt/edt/EditorOptionsText.ui
+++ b/src/edt/edt/EditorOptionsText.ui
@@ -1,7 +1,8 @@
-<ui version="4.0" >
+<?xml version="1.0" encoding="UTF-8"?>
+<ui version="4.0">
  <class>EditorOptionsText</class>
- <widget class="QWidget" name="EditorOptionsText" >
-  <property name="geometry" >
+ <widget class="QWidget" name="EditorOptionsText">
+  <property name="geometry">
    <rect>
     <x>0</x>
     <y>0</y>
@@ -9,225 +10,288 @@
     <height>243</height>
    </rect>
   </property>
-  <property name="windowTitle" >
+  <property name="windowTitle">
    <string>Form</string>
   </property>
-  <layout class="QVBoxLayout" >
-   <property name="margin" >
-    <number>9</number>
+  <layout class="QVBoxLayout">
+   <property name="spacing">
+    <number>2</number>
    </property>
-   <property name="spacing" >
-    <number>6</number>
+   <property name="leftMargin">
+    <number>0</number>
+   </property>
+   <property name="topMargin">
+    <number>0</number>
+   </property>
+   <property name="rightMargin">
+    <number>0</number>
+   </property>
+   <property name="bottomMargin">
+    <number>0</number>
    </property>
    <item>
-    <widget class="QFrame" name="frame" >
-     <property name="frameShape" >
+    <widget class="QScrollArea" name="scrollArea">
+     <property name="frameShape">
       <enum>QFrame::NoFrame</enum>
      </property>
-     <property name="frameShadow" >
-      <enum>QFrame::Raised</enum>
+     <property name="widgetResizable">
+      <bool>true</bool>
      </property>
-     <layout class="QGridLayout" >
-      <property name="margin" >
-       <number>9</number>
+     <widget class="QWidget" name="scrollAreaWidgetContents">
+      <property name="geometry">
+       <rect>
+        <x>0</x>
+        <y>0</y>
+        <width>542</width>
+        <height>243</height>
+       </rect>
       </property>
-      <property name="spacing" >
-       <number>6</number>
-      </property>
-      <item row="2" column="0" >
-       <widget class="QLabel" name="label_4" >
-        <property name="text" >
-         <string>Alignment</string>
-        </property>
-       </widget>
-      </item>
-      <item row="2" column="1" >
-       <widget class="QLabel" name="label_8" >
-        <property name="sizePolicy" >
-         <sizepolicy>
-          <hsizetype>0</hsizetype>
-          <vsizetype>5</vsizetype>
-          <horstretch>0</horstretch>
-          <verstretch>0</verstretch>
-         </sizepolicy>
-        </property>
-        <property name="text" >
-         <string>h =</string>
-        </property>
-       </widget>
-      </item>
-      <item row="3" column="0" >
-       <widget class="QLabel" name="Text size" >
-        <property name="text" >
-         <string>Text size</string>
-        </property>
-       </widget>
-      </item>
-      <item row="0" column="1" colspan="4" >
-       <widget class="QLineEdit" name="text_le" >
-        <property name="sizePolicy" >
-         <sizepolicy>
-          <hsizetype>7</hsizetype>
-          <vsizetype>0</vsizetype>
-          <horstretch>0</horstretch>
-          <verstretch>0</verstretch>
-         </sizepolicy>
-        </property>
-       </widget>
-      </item>
-      <item row="0" column="0" >
-       <widget class="QLabel" name="label_2" >
-        <property name="sizePolicy" >
-         <sizepolicy>
-          <hsizetype>0</hsizetype>
-          <vsizetype>5</vsizetype>
-          <horstretch>0</horstretch>
-          <verstretch>0</verstretch>
-         </sizepolicy>
-        </property>
-        <property name="text" >
-         <string>Text</string>
-        </property>
-       </widget>
-      </item>
-      <item row="4" column="1" colspan="4" >
-       <widget class="QLabel" name="label_3" >
-        <property name="text" >
-         <string>Hint: orientation, alignments and size cannot be saved to OASIS files
-Enable a vector font and text scaling in the setup dialog 
-to show text objects scaled and rotated</string>
-        </property>
-       </widget>
-      </item>
-      <item row="3" column="1" colspan="2" >
-       <widget class="QLineEdit" name="size_le" />
-      </item>
-      <item row="3" column="3" colspan="2" >
-       <widget class="QLabel" name="label" >
-        <property name="text" >
-         <string>(Leave empty for default)</string>
-        </property>
-       </widget>
-      </item>
-      <item row="2" column="4" >
-       <widget class="QComboBox" name="valign_cbx" >
-        <property name="sizePolicy" >
-         <sizepolicy>
-          <hsizetype>5</hsizetype>
-          <vsizetype>0</vsizetype>
-          <horstretch>1</horstretch>
-          <verstretch>0</verstretch>
-         </sizepolicy>
-        </property>
-        <item>
-         <property name="text" >
-          <string>(Default)</string>
+      <layout class="QGridLayout" name="gridLayout">
+       <item row="0" column="0">
+        <widget class="QFrame" name="frame">
+         <property name="frameShape">
+          <enum>QFrame::NoFrame</enum>
          </property>
-        </item>
-        <item>
-         <property name="text" >
-          <string>Top</string>
+         <property name="frameShadow">
+          <enum>QFrame::Raised</enum>
          </property>
-        </item>
-        <item>
-         <property name="text" >
-          <string>Center</string>
+         <layout class="QGridLayout" name="_2">
+          <property name="leftMargin">
+           <number>4</number>
+          </property>
+          <property name="topMargin">
+           <number>4</number>
+          </property>
+          <property name="rightMargin">
+           <number>4</number>
+          </property>
+          <property name="bottomMargin">
+           <number>4</number>
+          </property>
+          <property name="horizontalSpacing">
+           <number>6</number>
+          </property>
+          <property name="verticalSpacing">
+           <number>2</number>
+          </property>
+          <item row="2" column="3">
+           <widget class="QLabel" name="label_9">
+            <property name="sizePolicy">
+             <sizepolicy hsizetype="Fixed" vsizetype="Preferred">
+              <horstretch>0</horstretch>
+              <verstretch>0</verstretch>
+             </sizepolicy>
+            </property>
+            <property name="text">
+             <string>v =</string>
+            </property>
+           </widget>
+          </item>
+          <item row="1" column="0" colspan="5">
+           <spacer>
+            <property name="orientation">
+             <enum>Qt::Vertical</enum>
+            </property>
+            <property name="sizeType">
+             <enum>QSizePolicy::Fixed</enum>
+            </property>
+            <property name="sizeHint" stdset="0">
+             <size>
+              <width>20</width>
+              <height>5</height>
+             </size>
+            </property>
+           </spacer>
+          </item>
+          <item row="4" column="0">
+           <widget class="QLabel" name="Text size">
+            <property name="text">
+             <string>Text size</string>
+            </property>
+           </widget>
+          </item>
+          <item row="0" column="0">
+           <widget class="QLabel" name="label_2">
+            <property name="sizePolicy">
+             <sizepolicy hsizetype="Fixed" vsizetype="Preferred">
+              <horstretch>0</horstretch>
+              <verstretch>0</verstretch>
+             </sizepolicy>
+            </property>
+            <property name="text">
+             <string>Text</string>
+            </property>
+           </widget>
+          </item>
+          <item row="2" column="4">
+           <widget class="QComboBox" name="valign_cbx">
+            <property name="sizePolicy">
+             <sizepolicy hsizetype="Fixed" vsizetype="Fixed">
+              <horstretch>1</horstretch>
+              <verstretch>0</verstretch>
+             </sizepolicy>
+            </property>
+            <item>
+             <property name="text">
+              <string>(Default)</string>
+             </property>
+            </item>
+            <item>
+             <property name="text">
+              <string>Top</string>
+             </property>
+            </item>
+            <item>
+             <property name="text">
+              <string>Center</string>
+             </property>
+            </item>
+            <item>
+             <property name="text">
+              <string>Bottom</string>
+             </property>
+            </item>
+           </widget>
+          </item>
+          <item row="2" column="2">
+           <widget class="QComboBox" name="halign_cbx">
+            <property name="sizePolicy">
+             <sizepolicy hsizetype="Fixed" vsizetype="Fixed">
+              <horstretch>1</horstretch>
+              <verstretch>0</verstretch>
+             </sizepolicy>
+            </property>
+            <item>
+             <property name="text">
+              <string>(Default)</string>
+             </property>
+            </item>
+            <item>
+             <property name="text">
+              <string>Left</string>
+             </property>
+            </item>
+            <item>
+             <property name="text">
+              <string>Center</string>
+             </property>
+            </item>
+            <item>
+             <property name="text">
+              <string>Right</string>
+             </property>
+            </item>
+           </widget>
+          </item>
+          <item row="2" column="1">
+           <widget class="QLabel" name="label_8">
+            <property name="sizePolicy">
+             <sizepolicy hsizetype="Fixed" vsizetype="Preferred">
+              <horstretch>0</horstretch>
+              <verstretch>0</verstretch>
+             </sizepolicy>
+            </property>
+            <property name="text">
+             <string>h =</string>
+            </property>
+           </widget>
+          </item>
+          <item row="2" column="0">
+           <widget class="QLabel" name="label_4">
+            <property name="text">
+             <string>Alignment</string>
+            </property>
+           </widget>
+          </item>
+          <item row="2" column="5">
+           <spacer name="horizontalSpacer">
+            <property name="orientation">
+             <enum>Qt::Horizontal</enum>
+            </property>
+            <property name="sizeHint" stdset="0">
+             <size>
+              <width>40</width>
+              <height>20</height>
+             </size>
+            </property>
+           </spacer>
+          </item>
+          <item row="0" column="1" colspan="5">
+           <widget class="QLineEdit" name="text_le">
+            <property name="sizePolicy">
+             <sizepolicy hsizetype="Expanding" vsizetype="Fixed">
+              <horstretch>0</horstretch>
+              <verstretch>0</verstretch>
+             </sizepolicy>
+            </property>
+           </widget>
+          </item>
+          <item row="4" column="1" colspan="5">
+           <widget class="QFrame" name="frame_2">
+            <property name="frameShape">
+             <enum>QFrame::NoFrame</enum>
+            </property>
+            <property name="frameShadow">
+             <enum>QFrame::Raised</enum>
+            </property>
+            <layout class="QHBoxLayout" name="horizontalLayout">
+             <property name="leftMargin">
+              <number>0</number>
+             </property>
+             <property name="topMargin">
+              <number>0</number>
+             </property>
+             <property name="rightMargin">
+              <number>0</number>
+             </property>
+             <property name="bottomMargin">
+              <number>0</number>
+             </property>
+             <item>
+              <widget class="QLineEdit" name="size_le"/>
+             </item>
+             <item>
+              <widget class="QLabel" name="label">
+               <property name="text">
+                <string>(empty for default)</string>
+               </property>
+              </widget>
+             </item>
+            </layout>
+           </widget>
+          </item>
+          <item row="5" column="1" colspan="5">
+           <widget class="QLabel" name="label_3">
+            <property name="text">
+             <string>Hint: orientation, alignments and size cannot be saved to OASIS files. Enable a vector font and text scaling in the setup dialog to show text objects scaled and rotated.</string>
+            </property>
+            <property name="wordWrap">
+             <bool>true</bool>
+            </property>
+           </widget>
+          </item>
+         </layout>
+        </widget>
+       </item>
+       <item row="1" column="0">
+        <spacer name="spacer">
+         <property name="orientation">
+          <enum>Qt::Vertical</enum>
          </property>
-        </item>
-        <item>
-         <property name="text" >
-          <string>Bottom</string>
+         <property name="sizeHint" stdset="0">
+          <size>
+           <width>20</width>
+           <height>77</height>
+          </size>
          </property>
-        </item>
-       </widget>
-      </item>
-      <item row="2" column="3" >
-       <widget class="QLabel" name="label_9" >
-        <property name="sizePolicy" >
-         <sizepolicy>
-          <hsizetype>0</hsizetype>
-          <vsizetype>5</vsizetype>
-          <horstretch>0</horstretch>
-          <verstretch>0</verstretch>
-         </sizepolicy>
-        </property>
-        <property name="text" >
-         <string>v =</string>
-        </property>
-       </widget>
-      </item>
-      <item row="2" column="2" >
-       <widget class="QComboBox" name="halign_cbx" >
-        <property name="sizePolicy" >
-         <sizepolicy>
-          <hsizetype>5</hsizetype>
-          <vsizetype>0</vsizetype>
-          <horstretch>1</horstretch>
-          <verstretch>0</verstretch>
-         </sizepolicy>
-        </property>
-        <item>
-         <property name="text" >
-          <string>(Default)</string>
-         </property>
-        </item>
-        <item>
-         <property name="text" >
-          <string>Left</string>
-         </property>
-        </item>
-        <item>
-         <property name="text" >
-          <string>Center</string>
-         </property>
-        </item>
-        <item>
-         <property name="text" >
-          <string>Right</string>
-         </property>
-        </item>
-       </widget>
-      </item>
-      <item row="1" column="0" colspan="5" >
-       <spacer>
-        <property name="orientation" >
-         <enum>Qt::Vertical</enum>
-        </property>
-        <property name="sizeType" >
-         <enum>QSizePolicy::Fixed</enum>
-        </property>
-        <property name="sizeHint" >
-         <size>
-          <width>20</width>
-          <height>5</height>
-         </size>
-        </property>
-       </spacer>
-      </item>
-     </layout>
+        </spacer>
+       </item>
+      </layout>
+     </widget>
     </widget>
    </item>
-   <item>
-    <spacer>
-     <property name="orientation" >
-      <enum>Qt::Vertical</enum>
-     </property>
-     <property name="sizeHint" >
-      <size>
-       <width>20</width>
-       <height>40</height>
-      </size>
-     </property>
-    </spacer>
-   </item>
   </layout>
  </widget>
- <tabstops>
-  <tabstop>text_le</tabstop>
-  <tabstop>halign_cbx</tabstop>
-  <tabstop>valign_cbx</tabstop>
-  <tabstop>size_le</tabstop>
- </tabstops>
  <resources/>
  <connections/>
 </ui>
diff --git a/src/edt/edt/PCellParametersDialog.ui b/src/edt/edt/PCellParametersDialog.ui
deleted file mode 100644
index be3b83cde..000000000
--- a/src/edt/edt/PCellParametersDialog.ui
+++ /dev/null
@@ -1,73 +0,0 @@
-<?xml version="1.0" encoding="UTF-8"?>
-<ui version="4.0">
- <class>PCellParametersDialog</class>
- <widget class="QDialog" name="PCellParametersDialog">
-  <property name="geometry">
-   <rect>
-    <x>0</x>
-    <y>0</y>
-    <width>469</width>
-    <height>429</height>
-   </rect>
-  </property>
-  <property name="windowTitle">
-   <string>PCell Parameters</string>
-  </property>
-  <layout class="QVBoxLayout" name="verticalLayout">
-   <item>
-    <widget class="edt::PCellParametersPage" name="parameters" native="true"/>
-   </item>
-   <item>
-    <widget class="QDialogButtonBox" name="buttons">
-     <property name="standardButtons">
-      <set>QDialogButtonBox::Apply|QDialogButtonBox::Cancel|QDialogButtonBox::Ok</set>
-     </property>
-    </widget>
-   </item>
-  </layout>
- </widget>
- <layoutdefault spacing="6" margin="11"/>
- <customwidgets>
-  <customwidget>
-   <class>edt::PCellParametersPage</class>
-   <extends>QWidget</extends>
-   <header>edtPCellParametersPage.h</header>
-   <container>1</container>
-  </customwidget>
- </customwidgets>
- <resources/>
- <connections>
-  <connection>
-   <sender>buttons</sender>
-   <signal>rejected()</signal>
-   <receiver>PCellParametersDialog</receiver>
-   <slot>reject()</slot>
-   <hints>
-    <hint type="sourcelabel">
-     <x>321</x>
-     <y>405</y>
-    </hint>
-    <hint type="destinationlabel">
-     <x>337</x>
-     <y>423</y>
-    </hint>
-   </hints>
-  </connection>
-  <connection>
-   <sender>buttons</sender>
-   <signal>accepted()</signal>
-   <receiver>PCellParametersDialog</receiver>
-   <slot>accept()</slot>
-   <hints>
-    <hint type="sourcelabel">
-     <x>427</x>
-     <y>405</y>
-    </hint>
-    <hint type="destinationlabel">
-     <x>443</x>
-     <y>425</y>
-    </hint>
-   </hints>
-  </connection>
- </connections>
-</ui>
diff --git a/src/edt/edt/edt.pro b/src/edt/edt/edt.pro
index f72811940..5515e57c8 100644
--- a/src/edt/edt/edt.pro
+++ b/src/edt/edt/edt.pro
@@ -21,7 +21,8 @@ HEADERS = \
   edtServiceImpl.h \
   edtUtils.h \
     edtCommon.h \
-    edtPCellParametersDialog.h
+    edtDistribute.h \
+    edtRecentConfigurationPage.h
 
 FORMS = \
   AlignOptionsDialog.ui \
@@ -29,7 +30,6 @@ FORMS = \
   CopyModeDialog.ui \
   ChangeLayerOptionsDialog.ui \
   EditablePathPropertiesPage.ui \
-  EditorOptionsDialog.ui \
   EditorOptionsGeneric.ui \
   EditorOptionsInst.ui \
   EditorOptionsPath.ui \
@@ -42,7 +42,8 @@ FORMS = \
   PolygonPropertiesPage.ui \
   RoundCornerOptionsDialog.ui \
   TextPropertiesPage.ui \
-    PCellParametersDialog.ui
+    DistributeOptionsDialog.ui \
+    EditorOptionsInstPCellParam.ui
 
 SOURCES = \
   edtConfig.cc \
@@ -59,7 +60,8 @@ SOURCES = \
   edtServiceImpl.cc \
   edtUtils.cc \
   gsiDeclEdt.cc \
-    edtPCellParametersDialog.cc
+    edtDistribute.cc \
+    edtRecentConfigurationPage.cc
 
 INCLUDEPATH += $$TL_INC $$GSI_INC $$LAYBASIC_INC $$DB_INC
 DEPENDPATH += $$TL_INC $$GSI_INC $$LAYBASIC_INC $$DB_INC
diff --git a/src/edt/edt/edtDialogs.cc b/src/edt/edt/edtDialogs.cc
index 0fbc02113..21a0f6393 100644
--- a/src/edt/edt/edtDialogs.cc
+++ b/src/edt/edt/edtDialogs.cc
@@ -326,6 +326,93 @@ AlignOptionsDialog::exec_dialog (lay::LayoutView * /*view*/, int &hmode, int &vm
   }
 }
 
+// --------------------------------------------------------------------------------
+//  DistributeOptionsDialog implementation
+
+DistributeOptionsDialog::DistributeOptionsDialog (QWidget *parent)
+  : QDialog (parent)
+{
+  setObjectName (QString::fromUtf8 ("change_layer_options_dialog"));
+
+  Ui::DistributeOptionsDialog::setupUi (this);
+}
+
+DistributeOptionsDialog::~DistributeOptionsDialog ()
+{
+  //  .. nothing yet ..
+}
+
+bool
+DistributeOptionsDialog::exec_dialog (lay::LayoutView * /*view*/, bool &hdistribute, int &hmode, double &hpitch, double &hspace, bool &vdistribute, int &vmode, double &vpitch, double &vspace, bool &visible_layers)
+{
+  QRadioButton *hmode_buttons [] = { this->h_none_rb, this->h_left_rb, this->h_center_rb, this->h_right_rb };
+  QRadioButton *vmode_buttons [] = { this->v_none_rb, this->v_top_rb, this->v_center_rb, this->v_bottom_rb };
+  QRadioButton *layers_buttons [] = { this->all_layers_rb, this->visible_layers_rb };
+
+  this->h_distribute->setChecked (hdistribute);
+  for (int i = 1; i < 4; ++i) {
+    hmode_buttons [i]->setChecked (hmode == i);
+  }
+
+  this->h_space->setText (tl::to_qstring (tl::micron_to_string (hspace)));
+  this->h_pitch->setText (tl::to_qstring (tl::micron_to_string (hpitch)));
+
+  this->v_distribute->setChecked (vdistribute);
+  for (int i = 1; i < 4; ++i) {
+    vmode_buttons [i]->setChecked (vmode == i);
+  }
+
+  this->v_space->setText (tl::to_qstring (tl::micron_to_string (vspace)));
+  this->v_pitch->setText (tl::to_qstring (tl::micron_to_string (vpitch)));
+
+  for (int i = 0; i < 2; ++i) {
+    layers_buttons [i]->setChecked (int (visible_layers) == i);
+  }
+
+  if (QDialog::exec ()) {
+
+    hdistribute = this->h_distribute->isChecked ();
+    hmode = -1;
+    for (int i = 1; i < 4; ++i) {
+      if (hmode_buttons [i]->isChecked ()) {
+        hmode = i;
+      }
+    }
+
+    hspace = 0.0;
+    tl::from_string (tl::to_string (this->h_space->text ()), hspace);
+
+    hpitch = 0.0;
+    tl::from_string (tl::to_string (this->h_pitch->text ()), hpitch);
+
+    vdistribute = this->v_distribute->isChecked ();
+    vmode = -1;
+    for (int i = 1; i < 4; ++i) {
+      if (vmode_buttons [i]->isChecked ()) {
+        vmode = i;
+      }
+    }
+
+    vspace = 0.0;
+    tl::from_string (tl::to_string (this->v_space->text ()), vspace);
+
+    vpitch = 0.0;
+    tl::from_string (tl::to_string (this->v_pitch->text ()), vpitch);
+
+    visible_layers = false;
+    for (int i = 0; i < 2; ++i) {
+      if (layers_buttons [i]->isChecked ()) {
+        visible_layers = (i != 0);
+      }
+    }
+
+    return true;
+
+  } else {
+    return false;
+  }
+}
+
 // --------------------------------------------------------------------------------
 //  MakeCellOptionsDialog implementation
 
diff --git a/src/edt/edt/edtDialogs.h b/src/edt/edt/edtDialogs.h
index 4beddf680..15fc2fdf3 100644
--- a/src/edt/edt/edtDialogs.h
+++ b/src/edt/edt/edtDialogs.h
@@ -37,6 +37,7 @@
 #include "ui_InstantiationForm.h"
 #include "ui_ChangeLayerOptionsDialog.h"
 #include "ui_AlignOptionsDialog.h"
+#include "ui_DistributeOptionsDialog.h"
 #include "ui_CopyModeDialog.h"
 #include "ui_MakeCellOptionsDialog.h"
 #include "ui_MakeArrayOptionsDialog.h"
@@ -127,6 +128,22 @@ public:
   bool exec_dialog (lay::LayoutView *view, int &hmode, int &vmode, bool &visible_layers);
 };
 
+/**
+ *  @brief Distribute function options dialog
+ */
+class DistributeOptionsDialog
+  : public QDialog,
+    public Ui::DistributeOptionsDialog
+{
+Q_OBJECT
+
+public:
+  DistributeOptionsDialog (QWidget *parent);
+  virtual ~DistributeOptionsDialog ();
+
+  bool exec_dialog (lay::LayoutView *view, bool &hdistribute, int &hmode, double &hpitch, double &hspace, bool &vdistribute, int &vmode, double &vpitch, double &vspace, bool &visible_layers);
+};
+
 /**
  *  @brief Options dialog for the "make cell" function
  */
diff --git a/src/edt/edt/edtDistribute.cc b/src/edt/edt/edtDistribute.cc
new file mode 100644
index 000000000..1b3631cb2
--- /dev/null
+++ b/src/edt/edt/edtDistribute.cc
@@ -0,0 +1,27 @@
+
+/*
+
+  KLayout Layout Viewer
+  Copyright (C) 2006-2020 Matthias Koefferlein
+
+  This program is free software; you can redistribute it and/or modify
+  it under the terms of the GNU General Public License as published by
+  the Free Software Foundation; either version 2 of the License, or
+  (at your option) any later version.
+
+  This program is distributed in the hope that it will be useful,
+  but WITHOUT ANY WARRANTY; without even the implied warranty of
+  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+  GNU General Public License for more details.
+
+  You should have received a copy of the GNU General Public License
+  along with this program; if not, write to the Free Software
+  Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
+
+*/
+
+#include "edtDistribute.h"
+
+
+//  .. nothing yet (all in header) ..
+
diff --git a/src/edt/edt/edtDistribute.h b/src/edt/edt/edtDistribute.h
new file mode 100644
index 000000000..e7aad35eb
--- /dev/null
+++ b/src/edt/edt/edtDistribute.h
@@ -0,0 +1,476 @@
+/*
+
+  KLayout Layout Viewer
+  Copyright (C) 2006-2020 Matthias Koefferlein
+
+  This program is free software; you can redistribute it and/or modify
+  it under the terms of the GNU General Public License as published by
+  the Free Software Foundation; either version 2 of the License, or
+  (at your option) any later version.
+
+  This program is distributed in the hope that it will be useful,
+  but WITHOUT ANY WARRANTY; without even the implied warranty of
+  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+  GNU General Public License for more details.
+
+  You should have received a copy of the GNU General Public License
+  along with this program; if not, write to the Free Software
+  Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
+
+*/
+
+#ifndef HDR_edtDistribute
+#define HDR_edtDistribute
+
+#include "dbBox.h"
+
+#include "dbTypes.h"
+#include "tlIntervalMap.h"
+
+namespace edt
+{
+
+/**
+ *  @brief Gets the box position by reference position
+ */
+template <class Box, bool horizontally>
+typename Box::coord_type box_position (const Box &box, int ref)
+{
+  if (horizontally) {
+    if (ref < 0) {
+      return box.left ();
+    } else if (ref == 0) {
+      return box.center ().x ();
+    } else {
+      return box.right ();
+    }
+  } else {
+    if (ref < 0) {
+      return box.bottom ();
+    } else if (ref == 0) {
+      return box.center ().y ();
+    } else {
+      return box.top ();
+    }
+  }
+}
+
+/**
+ *  @brief Compares boxes by their reference position
+ */
+template <class Box, class Value, bool horizontally>
+class box_compare
+{
+public:
+  typedef typename Box::coord_type coord_type;
+
+  box_compare (int ref)
+    : m_ref (ref)
+  {
+    //  .. nothing yet ..
+  }
+
+  bool operator() (const std::pair<Box, Value> &a, const std::pair<Box, Value> &b) const
+  {
+    coord_type ca = box_position<Box, horizontally> (a.first, m_ref);
+    coord_type cb = box_position<Box, horizontally> (b.first, m_ref);
+
+    if (! db::coord_traits<coord_type>::equal (ca, cb)) {
+      return db::coord_traits<coord_type>::less (ca, cb);
+    } else {
+      coord_type ca2 = box_position<Box, !horizontally> (a.first, m_ref);
+      coord_type cb2 = box_position<Box, !horizontally> (b.first, m_ref);
+      return db::coord_traits<coord_type>::less (ca2, cb2);
+    }
+  }
+
+private:
+  int m_ref;
+};
+
+/**
+ *  @brief Does some heuristic binning of coordinates
+ */
+template <class Box, bool horizontally>
+void do_bin (typename std::vector<std::pair<Box, size_t> >::const_iterator b, typename std::vector<std::pair<Box, size_t> >::const_iterator e, int ref, std::vector<std::vector<size_t> > &bins)
+{
+  typedef typename Box::coord_type coord_type;
+
+  //  determine maximum distance between adjacent coordinates
+
+  coord_type max_dist = 0;
+  for (typename std::vector<std::pair<Box, size_t> >::const_iterator i = b + 1; i != e; ++i) {
+    max_dist = std::max (max_dist, box_position<Box, horizontally> (i->first, ref) - box_position<Box, horizontally> ((i - 1)->first, ref));
+  }
+
+  //  heuristically, everything that has a distance of less than 1/3 of the maximum distance falls into one bin
+
+  coord_type bin_start = box_position<Box, horizontally> (b->first, ref);
+  bins.push_back (std::vector<size_t> ());
+  bins.back ().push_back (b->second);
+
+  coord_type thr = max_dist / 3;
+
+  for (typename std::vector<std::pair<Box, size_t> >::const_iterator i = b + 1; i != e; ++i) {
+    coord_type c = box_position<Box, horizontally> (i->first, ref);
+    if (c - bin_start > thr) {
+      //  start a new bin
+      bins.push_back (std::vector<size_t> ());
+      bin_start = c;
+    }
+    bins.back ().push_back (i->second);
+  }
+}
+
+/**
+ * @brief Computes the effective box width (rounded to pitch, space added)
+ */
+template <class Box, bool horizontal>
+inline typename Box::coord_type eff_dim (const Box &box, typename Box::coord_type pitch, typename Box::coord_type space)
+{
+  typedef typename Box::coord_type coord_type;
+
+  coord_type d = (horizontal ? box.width () : box.height ()) + space;
+  if (pitch > 0) {
+    d = db::coord_traits<coord_type>::rounded (ceil (double (d) / double (pitch) - 1e-10) * double (pitch));
+  }
+  return d;
+}
+
+template <class Coord>
+struct max_coord_join_op
+{
+  void operator() (Coord &a, const Coord &b) const
+  {
+    a = std::max (a, b);
+  }
+};
+
+/**
+ *  @brief Implements an algorithm for 2d-distributing rectangular objects
+ */
+template <class Box, class Value>
+class distributed_placer
+{
+public:
+  typedef typename Box::coord_type coord_type;
+  typedef std::vector<std::pair<Box, Value> > objects;
+  typedef typename objects::const_iterator iterator;
+
+  /**
+   *  @brief Constructor
+   */
+  distributed_placer ()
+  {
+    //  .. nothing yet ..
+  }
+
+  /**
+   *  @brief Reserves space for n objects
+   */
+  void reserve (size_t n)
+  {
+    m_objects.reserve (n);
+  }
+
+  /**
+   *  @brief Inserts a new object
+   */
+  void insert (const Box &box, const Value &value)
+  {
+    tl_assert (! box.empty ());
+    m_objects.push_back (std::make_pair (box, value));
+  }
+
+  /**
+   *  @brief Stored objects iterator: begin
+   */
+  iterator begin () const
+  {
+    return m_objects.begin ();
+  }
+
+  /**
+   *  @brief Stored objects iterator: end
+   */
+  iterator end () const
+  {
+    return m_objects.end ();
+  }
+
+  /**
+   *  @brief Distributes the stored objects in vertical direction only
+   *
+   *  @param ref The reference location (-1: bottom, 0: center, 1: top)
+   *  @param refp The alignment in the other (horizontal) direction (-1: left, 0: center, 1: right, other: leave as is)
+   *  @param pitch The distribution pitch (grid) or 0 for no pitch
+   *  @param space The minimum space between the objects
+   */
+  void distribute_v (int ref, int refp, coord_type pitch, coord_type space)
+  {
+    do_distribute_1d<false> (ref, refp, pitch, space);
+  }
+
+  /**
+   *  @brief Distributes the stored objects in horizontal direction only
+   *
+   *  @param ref The reference location (-1: left, 0: center, 1: right)
+   *  @param refp The alignment in the other (vertical) direction (-1: bottom, 0: center, 1: top, other: leave as is)
+   *  @param pitch The distribution pitch (grid) or 0 for no pitch
+   *  @param space The minimum space between the objects
+   */
+  void distribute_h (int ref, int refp, coord_type pitch, coord_type space)
+  {
+    do_distribute_1d<true> (ref, refp, pitch, space);
+  }
+
+  /**
+   *  @brief Distributes the stored objects in horizontal and vertical direction
+   *
+   *  @param href The horizontal reference location (-1: left, 0: center, 1: right)
+   *  @param hpitch The horizontal distribution pitch (grid) or 0 for no pitch
+   *  @param hspace The horizontal minimum space between the objects
+   *  @param vref The vertical reference location (-1: bottom, 0: center, 1: top)
+   *  @param vpitch The vertical distribution pitch (grid) or 0 for no pitch
+   *  @param vspace The vertical minimum space between the objects
+   */
+  void distribute_matrix (int href, coord_type hpitch, coord_type hspace, int vref, coord_type vpitch, coord_type vspace)
+  {
+    if (m_objects.size () < 2) {
+      return;
+    }
+
+    //  The algorithm is this:
+    //  1.) Bin the boxes according to their positions in horizontal and vertical direction.
+    //      This forms the potential columns and rows
+    //  2.) Compute the row and column widths and heights as the maximum of their content
+    //  3.) position the objects inside these cells
+
+    std::vector<std::pair<Box, size_t> > indexed_boxes;
+    indexed_boxes.reserve (m_objects.size ());
+
+    Box all;
+    for (typename objects::iterator i = m_objects.begin (); i != m_objects.end (); ++i) {
+      all += i->first;
+    }
+
+    size_t n = 0;
+    for (typename objects::iterator i = m_objects.begin (); i != m_objects.end (); ++i, ++n) {
+      indexed_boxes.push_back (std::make_pair (i->first, n));
+    }
+
+    std::vector<std::vector<size_t> > hbins, vbins;
+
+    std::sort (indexed_boxes.begin (), indexed_boxes.end (), box_compare<Box, size_t, true> (href));
+    do_bin<Box, true> (indexed_boxes.begin (), indexed_boxes.end (), href, hbins);
+
+    std::sort (indexed_boxes.begin (), indexed_boxes.end (), box_compare<Box, size_t, false> (vref));
+    do_bin<Box, false> (indexed_boxes.begin (), indexed_boxes.end (), vref, vbins);
+
+    //  rewrite the bins to cell occupation lists
+
+    std::vector<std::vector<std::vector<size_t> > > cells;
+
+    cells.resize (hbins.size ());
+    for (size_t i = 0; i < hbins.size (); ++i) {
+      cells [i].resize (vbins.size ());
+    }
+
+    {
+
+      std::vector<size_t> hbin_for_index;
+      hbin_for_index.resize (indexed_boxes.size (), size_t (0));
+      for (std::vector<std::vector<size_t> >::const_iterator i = hbins.begin (); i != hbins.end (); ++i) {
+        for (std::vector<size_t>::const_iterator j = i->begin (); j != i->end (); ++j) {
+          hbin_for_index [*j] = i - hbins.begin ();
+        }
+      }
+
+      for (std::vector<std::vector<size_t> >::const_iterator i = vbins.begin (); i != vbins.end (); ++i) {
+        for (std::vector<size_t>::const_iterator j = i->begin (); j != i->end (); ++j) {
+          cells [hbin_for_index [*j]][i - vbins.begin ()].push_back (*j);
+        }
+      }
+
+    }
+
+    //  initialize the cell widths
+
+    std::vector<coord_type> cell_widths, cell_heights;
+    cell_widths.resize (hbins.size (), 0);
+    cell_heights.resize (vbins.size (), 0);
+
+    //  compute the cell widths as the maximum of the content
+
+    for (std::vector<std::vector<std::vector<size_t> > >::const_iterator i = cells.begin (); i != cells.end (); ++i) {
+
+      for (std::vector<std::vector<size_t> >::const_iterator j = i->begin (); j != i->end (); ++j) {
+
+        coord_type wcell = 0, hcell = 0;
+        for (std::vector<size_t>::const_iterator k = j->begin (); k != j->end (); ++k) {
+          //  NOTE: intra-cell objects are distributed horizontally
+          wcell += eff_dim<Box, true> (m_objects [*k].first, hpitch, hspace);
+          hcell = std::max (hcell, eff_dim<Box, false> (m_objects [*k].first, vpitch, vspace));
+        }
+
+        cell_widths [i - cells.begin ()] = std::max (cell_widths [i - cells.begin ()], wcell);
+        cell_heights [j - i->begin ()] = std::max (cell_heights [j - i->begin ()], hcell);
+
+      }
+
+    }
+
+    //  Compute the columns and row positions
+
+    std::vector<coord_type> cell_xpos, cell_ypos;
+    cell_xpos.reserve (cell_widths.size ());
+    cell_ypos.reserve (cell_heights.size ());
+
+    coord_type x = 0, y = 0;
+    for (typename std::vector<coord_type>::const_iterator i = cell_widths.begin (); i != cell_widths.end (); ++i) {
+      cell_xpos.push_back (x);
+      x += *i;
+    }
+    for (typename std::vector<coord_type>::const_iterator i = cell_heights.begin (); i != cell_heights.end (); ++i) {
+      cell_ypos.push_back (y);
+      y += *i;
+    }
+
+    //  Compute the actual coordinates of the objects inside the cells
+
+    for (std::vector<std::vector<std::vector<size_t> > >::const_iterator i = cells.begin (); i != cells.end (); ++i) {
+
+      for (std::vector<std::vector<size_t> >::const_iterator j = i->begin (); j != i->end (); ++j) {
+
+        coord_type wcell = 0;
+        for (std::vector<size_t>::const_iterator k = j->begin (); k != j->end (); ++k) {
+          //  NOTE: intra-cell objects are distributed horizontally
+          wcell += eff_dim<Box, true> (m_objects [*k].first, hpitch, hspace);
+        }
+
+        coord_type x = cell_xpos [i - cells.begin ()];
+        if (href == 0) {
+          x += (cell_widths [i - cells.begin ()] - wcell) / 2;
+        } else if (href > 0) {
+          x += (cell_widths [i - cells.begin ()] - wcell);
+        }
+
+        for (std::vector<size_t>::const_iterator k = j->begin (); k != j->end (); ++k) {
+
+          coord_type w = eff_dim<Box, true> (m_objects [*k].first, hpitch, hspace);
+          coord_type h = eff_dim<Box, false> (m_objects [*k].first, vpitch, vspace);
+
+          coord_type y = cell_ypos [j - i->begin ()];
+          if (vref == 0) {
+            y += (cell_heights [j - i->begin ()] - h) / 2;
+          } else if (href > 0) {
+            y += (cell_heights [j - i->begin ()] - h);
+          }
+
+          m_objects [*k].first.move (db::point<coord_type> (x, y) - m_objects [*k].first.p1 ());
+
+          //  NOTE: intra-cell objects are distributed horizontally
+          x += w;
+
+        }
+
+      }
+
+    }
+
+    //  Final adjustments - align the whole matrix with the original bounding box
+
+    Box new_all;
+    for (typename objects::iterator i = m_objects.begin (); i != m_objects.end (); ++i, ++n) {
+      new_all += i->first;
+    }
+
+    coord_type dh = box_position<Box, true> (all, href) - box_position<Box, true> (new_all, href);
+    coord_type dv = box_position<Box, false> (all, vref) - box_position<Box, false> (new_all, vref);
+    db::vector<coord_type> mv (dh, dv);
+
+    for (typename objects::iterator i = m_objects.begin (); i != m_objects.end (); ++i) {
+      i->first.move (mv);
+    }
+  }
+
+private:
+  objects m_objects;
+
+  template <bool horizontally>
+  void do_distribute_1d (int ref, int refp, coord_type pitch, coord_type space)
+  {
+    if (m_objects.size () < 2) {
+      return;
+    }
+
+    Box all;
+    for (typename objects::const_iterator i = m_objects.begin () + 1; i != m_objects.end (); ++i) {
+      all += i->first;
+    }
+
+    std::sort (m_objects.begin (), m_objects.end (), box_compare<Box, Value, horizontally> (ref));
+
+    Box current = m_objects.front ().first;
+    coord_type p0 = box_position<Box, horizontally> (current, ref);
+
+    for (typename objects::iterator i = m_objects.begin () + 1; i != m_objects.end (); ++i) {
+
+      coord_type p = box_position<Box, horizontally> (i->first, -1);
+      coord_type offset = box_position<Box, horizontally> (i->first, ref) - p;
+      coord_type pnew = box_position<Box, horizontally> (current, 1) + space;
+
+      if (db::coord_traits<coord_type>::less (0, pitch)) {
+        pnew = coord_type (ceil (double (pnew + offset - p0) / double (pitch) - 1e-10)) * pitch - offset + p0;
+      }
+
+      db::vector<coord_type> mv;
+      if (horizontally) {
+        mv = db::vector<coord_type> (pnew - p, 0);
+      } else {
+        mv = db::vector<coord_type> (0, pnew - p);
+      }
+
+      i->first.move (mv);
+      current = i->first;
+
+    }
+
+    //  final adjustment
+    Box new_all = m_objects.front ().first + m_objects.back ().first;
+
+    db::vector<coord_type> mv;
+    coord_type d = box_position<Box, horizontally> (all, ref) - box_position<Box, horizontally> (new_all, ref);
+    if (horizontally) {
+      mv = db::vector<coord_type> (d, 0);
+    } else {
+      mv = db::vector<coord_type> (0, d);
+    }
+
+    for (typename objects::iterator i = m_objects.begin (); i != m_objects.end (); ++i) {
+
+      i->first.move (mv);
+
+      if (refp >= -1 && refp <= 1) {
+
+        coord_type dp = box_position<Box, ! horizontally> (all, refp) - box_position<Box, ! horizontally> (i->first, refp);
+
+        db::vector<coord_type> mvp;
+        if (horizontally) {
+          mvp = db::vector<coord_type> (0, dp);
+        } else {
+          mvp = db::vector<coord_type> (dp, 0);
+        }
+
+        i->first.move (mvp);
+
+      }
+
+    }
+  }
+};
+
+}
+
+#endif
+
diff --git a/src/edt/edt/edtEditorOptionsPages.cc b/src/edt/edt/edtEditorOptionsPages.cc
index bd1940467..5cf86b819 100644
--- a/src/edt/edt/edtEditorOptionsPages.cc
+++ b/src/edt/edt/edtEditorOptionsPages.cc
@@ -25,209 +25,67 @@
 #include "dbLibrary.h"
 #include "dbLibraryManager.h"
 #include "dbPCellHeader.h"
-#include "edtEditorOptionsPages.h"
 #include "edtPCellParametersPage.h"
 #include "edtConfig.h"
 #include "edtService.h"
+#include "edtEditorOptionsPages.h"
+#include "edtPropertiesPageUtils.h"
 #include "tlExceptions.h"
 #include "layPlugin.h"
 #include "layLayoutView.h"
 #include "layCellSelectionForm.h"
-#include "ui_EditorOptionsDialog.h"
+#include "layQtTools.h"
 #include "ui_EditorOptionsGeneric.h"
 #include "ui_EditorOptionsPath.h"
 #include "ui_EditorOptionsText.h"
 #include "ui_EditorOptionsInst.h"
+#include "ui_EditorOptionsInstPCellParam.h"
+
+#include <QHBoxLayout>
+#include <QVBoxLayout>
+#include <QTabWidget>
+#include <QToolButton>
+#include <QCompleter>
 
 namespace edt
 {
 
 // ------------------------------------------------------------------
-//  EditorOptionsPage implementation
+//  Configures a value from a line edit
 
-EditorOptionsPage::EditorOptionsPage ()
-  : mp_owner (0), m_active (true), mp_plugin_declaration (0)
-{
-  //  nothing yet ..
-}
-
-EditorOptionsPage::~EditorOptionsPage ()
-{
-  set_owner (0);
-}
-
-void 
-EditorOptionsPage::set_owner (EditorOptionsPages *owner)
-{
-  if (mp_owner) {
-    mp_owner->unregister_page (this);
-  }
-  mp_owner = owner;
-}
-
-void  
-EditorOptionsPage::activate (bool active)
-{
-  if (m_active != active) {
-    m_active = active;
-    if (mp_owner) {
-      mp_owner->activate_page (this);
-    }
-  }
-}
-
-// ------------------------------------------------------------------
-//  EditorOptionsPages implementation
-
-struct EOPCompareOp
-{
-  bool operator() (edt::EditorOptionsPage *a, edt::EditorOptionsPage *b) const
-  {
-    return a->order () < b->order ();
-  }
-};
-
-EditorOptionsPages::EditorOptionsPages (const std::vector<edt::EditorOptionsPage *> &pages, lay::Dispatcher *root)
-  : mp_root (root)
-{
-  mp_ui = new Ui::EditorOptionsDialog ();
-  mp_ui->setupUi (this);
-
-  connect (mp_ui->apply_pb, SIGNAL (clicked ()), this, SLOT (apply ()));
-
-  m_pages = pages;
-  for (std::vector <edt::EditorOptionsPage *>::const_iterator p = m_pages.begin (); p != m_pages.end (); ++p) {
-    (*p)->set_owner (this);
-  }
-
-  update (0);
-  setup ();
-}
-
-EditorOptionsPages::~EditorOptionsPages ()
-{
-  while (m_pages.size () > 0) {
-    delete m_pages [0];
-  }
-
-  delete mp_ui;
-  mp_ui = 0;
-}
-
-void  
-EditorOptionsPages::unregister_page (edt::EditorOptionsPage *page)
-{
-  std::vector <edt::EditorOptionsPage *> pages;
-  for (std::vector <edt::EditorOptionsPage *>::const_iterator p = m_pages.begin (); p != m_pages.end (); ++p) {
-    if (*p != page) {
-      pages.push_back (*p);
-    }
-  }
-  m_pages = pages;
-  update (0);
-}
-
-void  
-EditorOptionsPages::activate_page (edt::EditorOptionsPage *page)
+template <class Value>
+static void configure_from_line_edit (lay::Dispatcher *dispatcher, QLineEdit *le, const std::string &cfg_name)
 {
   try {
-    page->setup (mp_root);
-  } catch (...) {
-    //  catch any errors related to configuration file errors etc.
+    Value value = Value (0);
+    tl::from_string (tl::to_string (le->text ()), value);
+    dispatcher->config_set (cfg_name, tl::to_string (value));
+    lay::indicate_error (le, 0);
+  } catch (tl::Exception &ex) {
+    lay::indicate_error (le, &ex);
   }
-  update (page);
-
-  if (isVisible ()) {
-    activateWindow ();
-    raise ();
-  }
-}
-
-void   
-EditorOptionsPages::update (edt::EditorOptionsPage *page)
-{
-  std::sort (m_pages.begin (), m_pages.end (), EOPCompareOp ());
-
-  while (mp_ui->pages->count () > 0) {
-    mp_ui->pages->removeTab (0);
-  }
-  int index = -1;
-  for (std::vector <edt::EditorOptionsPage *>::iterator p = m_pages.begin (); p != m_pages.end (); ++p) {
-    if ((*p)->active ()) {
-      mp_ui->pages->addTab ((*p)->q_frame (), tl::to_qstring ((*p)->title ()));
-      if ((*p) == page) {
-        index = int (std::distance (m_pages.begin (), p));
-      }
-    } else {
-      (*p)->q_frame ()->setParent (0);
-    }
-  }
-  if (index < 0) {
-    index = mp_ui->pages->currentIndex ();
-  }
-  if (index >= int (mp_ui->pages->count ())) {
-    index = mp_ui->pages->count () - 1;
-  }
-  mp_ui->pages->setCurrentIndex (index);
-}
-
-void 
-EditorOptionsPages::setup ()
-{
-  try {
-
-    for (std::vector <edt::EditorOptionsPage *>::iterator p = m_pages.begin (); p != m_pages.end (); ++p) {
-      if ((*p)->active ()) {
-        (*p)->setup (mp_root);
-      }
-    }
-
-    //  make the display consistent with the status (this is important for 
-    //  PCell parameters where the PCell may be asked to modify the parameters)
-    do_apply ();
-
-  } catch (...) {
-    //  catch any errors related to configuration file errors etc.
-  }
-}
-
-void 
-EditorOptionsPages::do_apply ()
-{
-  for (std::vector <edt::EditorOptionsPage *>::iterator p = m_pages.begin (); p != m_pages.end (); ++p) {
-    if ((*p)->active ()) {
-      (*p)->apply (mp_root);
-    }
-  }
-}
-
-void 
-EditorOptionsPages::apply ()
-{
-BEGIN_PROTECTED
-  do_apply ();
-END_PROTECTED_W (this)
-}
-
-void
-EditorOptionsPages::accept ()
-{
-BEGIN_PROTECTED
-  do_apply ();
-  QDialog::accept ();
-END_PROTECTED_W (this)
 }
 
 // ------------------------------------------------------------------
 //  EditorOptionsGeneric implementation
 
-EditorOptionsGeneric::EditorOptionsGeneric ()
-  : QWidget (), EditorOptionsPage ()
+EditorOptionsGeneric::EditorOptionsGeneric (lay::Dispatcher *dispatcher)
+  : EditorOptionsPage (dispatcher)
 {
   mp_ui = new Ui::EditorOptionsGeneric ();
   mp_ui->setupUi (this);
 
   connect (mp_ui->grid_cb, SIGNAL (activated (int)), this, SLOT (grid_changed (int)));
+
+  connect (mp_ui->edit_grid_le, SIGNAL (editingFinished ()), this, SLOT (edited ()));
+  connect (mp_ui->grid_cb, SIGNAL (activated (int)), this, SLOT (edited ()));
+  connect (mp_ui->move_angle_cb, SIGNAL (activated (int)), this, SLOT (edited ()));
+  connect (mp_ui->conn_angle_cb, SIGNAL (activated (int)), this, SLOT (edited ()));
+  connect (mp_ui->hier_sel_cbx, SIGNAL (clicked ()), this, SLOT (edited ()));
+  connect (mp_ui->hier_copy_mode_cbx, SIGNAL (activated (int)), this, SLOT (edited ()));
+  connect (mp_ui->snap_objects_cbx, SIGNAL (clicked ()), this, SLOT (edited ()));
+  connect (mp_ui->max_shapes_le, SIGNAL (editingFinished ()), this, SLOT (edited ()));
+  connect (mp_ui->show_shapes_cbx, SIGNAL (clicked ()), this, SLOT (edited ()));
 }
 
 EditorOptionsGeneric::~EditorOptionsGeneric ()
@@ -236,27 +94,32 @@ EditorOptionsGeneric::~EditorOptionsGeneric ()
   mp_ui = 0;
 }
 
-std::string 
+std::string
 EditorOptionsGeneric::title () const
 {
   return tl::to_string (QObject::tr ("Basic Editing"));
 }
 
-void  
-EditorOptionsGeneric::apply (lay::Plugin *root) 
+void
+EditorOptionsGeneric::apply (lay::Dispatcher *root)
 {
   //  Edit grid
-  
-  db::DVector eg;
+
   EditGridConverter egc;
   if (mp_ui->grid_cb->currentIndex () == 0) {
-    eg = db::DVector (-1.0, -1.0);
+    root->config_set (cfg_edit_grid, egc.to_string (db::DVector (-1.0, -1.0)));
   } else if (mp_ui->grid_cb->currentIndex () == 1) {
-    eg = db::DVector ();
+    root->config_set (cfg_edit_grid, egc.to_string (db::DVector ()));
   } else {
-    egc.from_string_picky (tl::to_string (mp_ui->edit_grid_le->text ()), eg);
+    try {
+      db::DVector eg;
+      egc.from_string_picky (tl::to_string (mp_ui->edit_grid_le->text ()), eg);
+      lay::indicate_error (mp_ui->edit_grid_le, 0);
+      root->config_set (cfg_edit_grid, egc.to_string (eg));
+    } catch (tl::Exception &ex) {
+      lay::indicate_error (mp_ui->edit_grid_le, &ex);
+    }
   }
-  root->config_set (cfg_edit_grid, egc.to_string (eg));
 
   //  Edit & move angle
 
@@ -269,9 +132,7 @@ EditorOptionsGeneric::apply (lay::Plugin *root)
   root->config_set (cfg_edit_hier_copy_mode, tl::to_string ((cpm < 0 || cpm > 1) ? -1 : cpm));
   root->config_set (cfg_edit_snap_to_objects, tl::to_string (mp_ui->snap_objects_cbx->isChecked ()));
 
-  unsigned int max_shapes = 1000;
-  tl::from_string (tl::to_string (mp_ui->max_shapes_le->text ()), max_shapes);
-  root->config_set (cfg_edit_max_shapes_of_instances, tl::to_string (max_shapes));
+  configure_from_line_edit<unsigned int> (root, mp_ui->max_shapes_le, cfg_edit_max_shapes_of_instances);
   root->config_set (cfg_edit_show_shapes_of_instances, tl::to_string (mp_ui->show_shapes_cbx->isChecked ()));
 }
 
@@ -287,8 +148,8 @@ EditorOptionsGeneric::show_shapes_changed ()
   mp_ui->max_shapes_le->setEnabled (mp_ui->show_shapes_cbx->isChecked ());
 }
 
-void  
-EditorOptionsGeneric::setup (lay::Plugin *root)
+void
+EditorOptionsGeneric::setup (lay::Dispatcher *root)
 {
   //  Edit grid
 
@@ -305,12 +166,13 @@ EditorOptionsGeneric::setup (lay::Plugin *root)
     mp_ui->edit_grid_le->setText (tl::to_qstring (egc.to_string (eg)));
   }
   grid_changed (mp_ui->grid_cb->currentIndex ());
+  lay::indicate_error (mp_ui->edit_grid_le, 0);
 
   //  edit & move angle
 
   ACConverter acc;
   lay::angle_constraint_type ac;
-  
+
   ac = lay::AC_Any;
   root->config_get (cfg_edit_move_angle_mode, ac, acc);
   mp_ui->move_angle_cb->setCurrentIndex (int (ac));
@@ -334,6 +196,7 @@ EditorOptionsGeneric::setup (lay::Plugin *root)
   unsigned int max_shapes = 1000;
   root->config_get (cfg_edit_max_shapes_of_instances, max_shapes);
   mp_ui->max_shapes_le->setText (tl::to_qstring (tl::to_string (max_shapes)));
+  lay::indicate_error (mp_ui->max_shapes_le, 0);
 
   bool show_shapes = true;
   root->config_get (cfg_edit_show_shapes_of_instances, show_shapes);
@@ -343,11 +206,16 @@ EditorOptionsGeneric::setup (lay::Plugin *root)
 // ------------------------------------------------------------------
 //  EditorOptionsText implementation
 
-EditorOptionsText::EditorOptionsText ()
-  : QWidget (), EditorOptionsPage ()
+EditorOptionsText::EditorOptionsText (lay::Dispatcher *dispatcher)
+  : lay::EditorOptionsPage (dispatcher)
 {
   mp_ui = new Ui::EditorOptionsText ();
   mp_ui->setupUi (this);
+
+  connect (mp_ui->text_le, SIGNAL (editingFinished ()), this, SLOT (edited ()));
+  connect (mp_ui->halign_cbx, SIGNAL (activated (int)), this, SLOT (edited ()));
+  connect (mp_ui->valign_cbx, SIGNAL (activated (int)), this, SLOT (edited ()));
+  connect (mp_ui->size_le, SIGNAL (editingFinished ()), this, SLOT (edited ()));
 }
 
 EditorOptionsText::~EditorOptionsText ()
@@ -363,7 +231,7 @@ EditorOptionsText::title () const
 }
 
 void  
-EditorOptionsText::apply (lay::Plugin *root) 
+EditorOptionsText::apply (lay::Dispatcher *root)
 {
   //  Text string
   root->config_set (cfg_edit_text_string, tl::unescape_string (tl::to_string (mp_ui->text_le->text ())));
@@ -387,7 +255,7 @@ EditorOptionsText::apply (lay::Plugin *root)
 }
 
 void  
-EditorOptionsText::setup (lay::Plugin *root)
+EditorOptionsText::setup (lay::Dispatcher *root)
 {
   //  Text string
   std::string s;
@@ -416,13 +284,18 @@ EditorOptionsText::setup (lay::Plugin *root)
 // ------------------------------------------------------------------
 //  EditorOptionsPath implementation
 
-EditorOptionsPath::EditorOptionsPath ()
-  : QWidget (), EditorOptionsPage ()
+EditorOptionsPath::EditorOptionsPath (lay::Dispatcher *dispatcher)
+  : lay::EditorOptionsPage (dispatcher)
 {
   mp_ui = new Ui::EditorOptionsPath ();
   mp_ui->setupUi (this);
 
   connect (mp_ui->type_cb, SIGNAL (currentIndexChanged (int)), this, SLOT (type_changed (int)));
+
+  connect (mp_ui->width_le, SIGNAL (editingFinished ()), this, SLOT (edited ()));
+  connect (mp_ui->type_cb, SIGNAL (activated (int)), this, SLOT (edited ()));
+  connect (mp_ui->start_ext_le, SIGNAL (editingFinished ()), this, SLOT (edited ()));
+  connect (mp_ui->end_ext_le, SIGNAL (editingFinished ()), this, SLOT (edited ()));
 }
 
 EditorOptionsPath::~EditorOptionsPath ()
@@ -445,13 +318,11 @@ EditorOptionsPath::type_changed (int type)
 }
 
 void  
-EditorOptionsPath::apply (lay::Plugin *root) 
+EditorOptionsPath::apply (lay::Dispatcher *root)
 {
   //  width
 
-  double w = 0.0;
-  tl::from_string (tl::to_string (mp_ui->width_le->text ()), w);
-  root->config_set (cfg_edit_path_width, tl::to_string (w));
+  configure_from_line_edit<double> (root, mp_ui->width_le, cfg_edit_path_width);
 
   //  path type and extensions 
 
@@ -465,14 +336,10 @@ EditorOptionsPath::apply (lay::Plugin *root)
 
   } else if (mp_ui->type_cb->currentIndex () == 2) {
 
-    double bgnext = 0.0, endext = 0.0;
     root->config_set (cfg_edit_path_ext_type, "variable");
 
-    tl::from_string (tl::to_string (mp_ui->start_ext_le->text ()), bgnext);
-    root->config_set (cfg_edit_path_ext_var_begin, tl::to_string (bgnext));
-
-    tl::from_string (tl::to_string (mp_ui->end_ext_le->text ()), endext);
-    root->config_set (cfg_edit_path_ext_var_end, tl::to_string (endext));
+    configure_from_line_edit<double> (root, mp_ui->start_ext_le, cfg_edit_path_ext_var_begin);
+    configure_from_line_edit<double> (root, mp_ui->end_ext_le, cfg_edit_path_ext_var_end);
 
   } else if (mp_ui->type_cb->currentIndex () == 3) {
 
@@ -482,13 +349,14 @@ EditorOptionsPath::apply (lay::Plugin *root)
 }
 
 void  
-EditorOptionsPath::setup (lay::Plugin *root)
+EditorOptionsPath::setup (lay::Dispatcher *root)
 {
   //  width
 
   double w = 0.0;
   root->config_get (cfg_edit_path_width, w);
   mp_ui->width_le->setText (tl::to_qstring (tl::to_string (w)));
+  lay::indicate_error (mp_ui->width_le, 0);
 
   //  path type and extensions 
 
@@ -509,26 +377,35 @@ EditorOptionsPath::setup (lay::Plugin *root)
   root->config_get (cfg_edit_path_ext_var_begin, bgnext);
   root->config_get (cfg_edit_path_ext_var_end, endext);
   mp_ui->start_ext_le->setText (tl::to_qstring (tl::to_string (bgnext)));
+  lay::indicate_error (mp_ui->start_ext_le, 0);
   mp_ui->end_ext_le->setText (tl::to_qstring (tl::to_string (endext)));
+  lay::indicate_error (mp_ui->end_ext_le, 0);
 }
 
 // ------------------------------------------------------------------
 //  EditorOptionsInst implementation
 
-EditorOptionsInst::EditorOptionsInst (lay::Dispatcher *root)
-  : QWidget (), EditorOptionsPage (), mp_root (root), mp_pcell_parameters (0)
+EditorOptionsInst::EditorOptionsInst (lay::Dispatcher *dispatcher)
+  : lay::EditorOptionsPage (dispatcher)
 {
   mp_ui = new Ui::EditorOptionsInst ();
   mp_ui->setupUi (this);
 
   connect (mp_ui->array_grp, SIGNAL (clicked ()), this, SLOT (array_changed ()));
   connect (mp_ui->browse_pb, SIGNAL (clicked ()), this, SLOT (browse_cell ()));
-  connect (mp_ui->lib_cbx, SIGNAL (currentIndexChanged (int)), this, SLOT (library_changed (int)));
-  connect (mp_ui->cell_le, SIGNAL (textChanged (const QString &)), this, SLOT (cell_name_changed (const QString &)));
-
-  QHBoxLayout *layout = new QHBoxLayout (mp_ui->pcell_tab);
-  layout->setMargin (0);
-  mp_ui->pcell_tab->setLayout (layout);
+  connect (mp_ui->lib_cbx, SIGNAL (currentIndexChanged (int)), this, SLOT (library_changed ()));
+  connect (mp_ui->cell_le, SIGNAL (editingFinished ()), this, SLOT (edited ()));
+  connect (mp_ui->angle_le, SIGNAL (editingFinished ()), this, SLOT (edited ()));
+  connect (mp_ui->scale_le, SIGNAL (editingFinished ()), this, SLOT (edited ()));
+  connect (mp_ui->rows_le, SIGNAL (editingFinished ()), this, SLOT (edited ()));
+  connect (mp_ui->row_x_le, SIGNAL (editingFinished ()), this, SLOT (edited ()));
+  connect (mp_ui->row_y_le, SIGNAL (editingFinished ()), this, SLOT (edited ()));
+  connect (mp_ui->columns_le, SIGNAL (editingFinished ()), this, SLOT (edited ()));
+  connect (mp_ui->column_x_le, SIGNAL (editingFinished ()), this, SLOT (edited ()));
+  connect (mp_ui->column_y_le, SIGNAL (editingFinished ()), this, SLOT (edited ()));
+  connect (mp_ui->mirror_cbx, SIGNAL (clicked ()), this, SLOT (edited ()));
+  connect (mp_ui->array_grp, SIGNAL (clicked ()), this, SLOT (edited ()));
+  connect (mp_ui->place_origin_cb, SIGNAL (clicked ()), this, SLOT (edited ()));
 
   m_cv_index = -1;
 }
@@ -546,19 +423,61 @@ EditorOptionsInst::title () const
 }
 
 void
-EditorOptionsInst::library_changed (int)
+EditorOptionsInst::library_changed ()
 {
-BEGIN_PROTECTED
-  update_pcell_parameters ();
-END_PROTECTED
+  update_cell_edits ();
+  edited ();
 }
 
+//  Maximum number of cells for which to offer a cell name completer
+const static size_t max_cells = 10000;
+
 void
-EditorOptionsInst::cell_name_changed (const QString &)
+EditorOptionsInst::update_cell_edits ()
 {
-BEGIN_PROTECTED
-  update_pcell_parameters ();
-END_PROTECTED
+  if (mp_ui->cell_le->completer ()) {
+    mp_ui->cell_le->completer ()->deleteLater ();
+  }
+
+  db::Layout *layout = 0;
+  lay::LayoutView *view = lay::LayoutView::current ();
+
+  //  find the layout the cell has to be looked up: that is either the layout of the current instance or
+  //  the library selected
+  if (mp_ui->lib_cbx->current_library ()) {
+    layout = &mp_ui->lib_cbx->current_library ()->layout ();
+  } else if (view && view->cellview (m_cv_index).is_valid ()) {
+    layout = &view->cellview (m_cv_index)->layout ();
+  }
+
+  if (! layout) {
+    return;
+  }
+
+  QStringList cellnames;
+  if (layout->cells () < max_cells) {
+    for (db::Layout::iterator c = layout->begin (); c != layout->end (); ++c) {
+      cellnames.push_back (tl::to_qstring (layout->cell_name (c->cell_index ())));
+    }
+    for (db::Layout::pcell_iterator pc = layout->begin_pcells (); pc != layout->end_pcells () && size_t (cellnames.size ()) < max_cells; ++pc) {
+      cellnames.push_back (tl::to_qstring (pc->first));
+    }
+  }
+
+  if (size_t (cellnames.size ()) < max_cells) {
+    QCompleter *completer = new QCompleter (cellnames, this);
+    completer->setCaseSensitivity (Qt::CaseSensitive);
+    mp_ui->cell_le->setCompleter (completer);
+  } else {
+    mp_ui->cell_le->setCompleter (0);
+  }
+
+  std::pair<bool, db::pcell_id_type> pc = layout->pcell_by_name (tl::to_string (mp_ui->cell_le->text ()).c_str ());
+  std::pair<bool, db::cell_index_type> cc = layout->cell_by_name (tl::to_string (mp_ui->cell_le->text ()).c_str ());
+
+  //  by the way, update the foreground color of the cell edit box as well (red, if not valid)
+  tl::Exception ex ("No cell or PCell with this name");
+  lay::indicate_error (mp_ui->cell_le, (! pc.first && ! cc.first) ? &ex : 0);
 }
 
 void
@@ -602,7 +521,7 @@ BEGIN_PROTECTED
       } else if (layout->is_valid_cell_index (form.selected_cell_index ())) {
         mp_ui->cell_le->setText (tl::to_qstring (layout->cell_name (form.selected_cell_index ())));
       }
-      update_pcell_parameters ();
+      edited ();
     }
 
   }
@@ -620,74 +539,40 @@ EditorOptionsInst::array_changed ()
   mp_ui->columns_le->setEnabled (array);
   mp_ui->column_x_le->setEnabled (array);
   mp_ui->column_y_le->setEnabled (array);
+  edited ();
 }
 
 void  
-EditorOptionsInst::apply (lay::Plugin *root) 
+EditorOptionsInst::apply (lay::Dispatcher *root)
 {
   //  cell name
   root->config_set (cfg_edit_inst_cell_name, tl::to_string (mp_ui->cell_le->text ()));
 
-  //  cell name
+  //  lib name
   if (mp_ui->lib_cbx->current_library ()) {
     root->config_set (cfg_edit_inst_lib_name, mp_ui->lib_cbx->current_library ()->get_name ());
   } else {
     root->config_set (cfg_edit_inst_lib_name, std::string ());
   }
 
-  //  pcell parameters
-  std::string param;
-  db::Layout *layout = 0;
-
-  if (mp_ui->lib_cbx->current_library ()) {
-    layout = &mp_ui->lib_cbx->current_library ()->layout ();
-  } else if (m_cv_index >= 0 && lay::LayoutView::current () && lay::LayoutView::current ()->cellview (m_cv_index).is_valid ()) {
-    layout = &lay::LayoutView::current ()->cellview (m_cv_index)->layout ();
-  }
-
-  if (layout && mp_pcell_parameters) {
-    std::pair<bool, db::pcell_id_type> pc = layout->pcell_by_name (tl::to_string (mp_ui->cell_le->text ()).c_str ());
-    if (pc.first) {
-      const db::PCellDeclaration *pc_decl = layout->pcell_declaration (pc.second);
-      if (pc_decl) {
-        param = pcell_parameters_to_string (pc_decl->named_parameters (mp_pcell_parameters->get_parameters ()));
-      }
-    }
-  }
-  
-  root->config_set (cfg_edit_inst_pcell_parameters, param);
-
   //  rotation, scaling
-  double angle = 0.0;
-  tl::from_string (tl::to_string (mp_ui->angle_le->text ()), angle);
-  root->config_set (cfg_edit_inst_angle, tl::to_string (angle));
+  configure_from_line_edit<double> (root, mp_ui->angle_le, cfg_edit_inst_angle);
 
   bool mirror = mp_ui->mirror_cbx->isChecked ();
   root->config_set (cfg_edit_inst_mirror, tl::to_string (mirror));
 
-  double scale = 1.0;
-  tl::from_string (tl::to_string (mp_ui->scale_le->text ()), scale);
-  root->config_set (cfg_edit_inst_scale, tl::to_string (scale));
+  configure_from_line_edit<double> (root, mp_ui->scale_le, cfg_edit_inst_scale);
 
   //  array
   bool array = mp_ui->array_grp->isChecked ();
   root->config_set (cfg_edit_inst_array, tl::to_string (array));
 
-  int rows = 1, columns = 1;
-  double row_x = 0.0, row_y = 0.0, column_x = 0.0, column_y = 0.0;
-  tl::from_string (tl::to_string (mp_ui->rows_le->text ()), rows);
-  tl::from_string (tl::to_string (mp_ui->row_x_le->text ()), row_x);
-  tl::from_string (tl::to_string (mp_ui->row_y_le->text ()), row_y);
-  tl::from_string (tl::to_string (mp_ui->columns_le->text ()), columns);
-  tl::from_string (tl::to_string (mp_ui->column_x_le->text ()), column_x);
-  tl::from_string (tl::to_string (mp_ui->column_y_le->text ()), column_y);
-
-  root->config_set (cfg_edit_inst_rows, tl::to_string (rows));
-  root->config_set (cfg_edit_inst_row_x, tl::to_string (row_x));
-  root->config_set (cfg_edit_inst_row_y, tl::to_string (row_y));
-  root->config_set (cfg_edit_inst_columns, tl::to_string (columns));
-  root->config_set (cfg_edit_inst_column_x, tl::to_string (column_x));
-  root->config_set (cfg_edit_inst_column_y, tl::to_string (column_y));
+  configure_from_line_edit<int> (root, mp_ui->rows_le, cfg_edit_inst_rows);
+  configure_from_line_edit<double> (root, mp_ui->row_x_le, cfg_edit_inst_row_x);
+  configure_from_line_edit<double> (root, mp_ui->row_y_le, cfg_edit_inst_row_y);
+  configure_from_line_edit<int> (root, mp_ui->columns_le, cfg_edit_inst_columns);
+  configure_from_line_edit<double> (root, mp_ui->column_x_le, cfg_edit_inst_column_x);
+  configure_from_line_edit<double> (root, mp_ui->column_y_le, cfg_edit_inst_column_y);
 
   //  place origin of cell flag
   bool place_origin = mp_ui->place_origin_cb->isChecked ();
@@ -695,45 +580,187 @@ EditorOptionsInst::apply (lay::Plugin *root)
 }
 
 void  
-EditorOptionsInst::setup (lay::Plugin *root)
+EditorOptionsInst::setup (lay::Dispatcher *root)
 {
   m_cv_index = -1;
   if (lay::LayoutView::current ()) {
     m_cv_index = lay::LayoutView::current ()->active_cellview_index ();
   }
-  mp_ui->lib_cbx->update_list ();
-  if (m_cv_index >= 0 && lay::LayoutView::current () && lay::LayoutView::current ()->cellview (m_cv_index).is_valid ()) {
-    mp_ui->lib_cbx->set_technology_filter (lay::LayoutView::current ()->cellview (m_cv_index)->tech_name (), true);
-  } else {
-    mp_ui->lib_cbx->set_technology_filter (std::string (), false);
+
+  try {
+
+    mp_ui->lib_cbx->blockSignals (true);
+
+    mp_ui->lib_cbx->update_list ();
+    if (m_cv_index >= 0 && lay::LayoutView::current () && lay::LayoutView::current ()->cellview (m_cv_index).is_valid ()) {
+      mp_ui->lib_cbx->set_technology_filter (lay::LayoutView::current ()->cellview (m_cv_index)->tech_name (), true);
+    } else {
+      mp_ui->lib_cbx->set_technology_filter (std::string (), false);
+    }
+
+    //  cell name
+    std::string s;
+    root->config_get (cfg_edit_inst_cell_name, s);
+    mp_ui->cell_le->setText (tl::to_qstring (s));
+
+    //  library
+    std::string l;
+    root->config_get (cfg_edit_inst_lib_name, l);
+    mp_ui->lib_cbx->set_current_library (db::LibraryManager::instance ().lib_ptr_by_name (l));
+
+    mp_ui->lib_cbx->blockSignals (false);
+    update_cell_edits ();
+
+  } catch (...) {
+    mp_ui->lib_cbx->blockSignals (false);
+    throw;
   }
 
+  //  rotation, scaling
+  double angle = 0.0;
+  root->config_get (cfg_edit_inst_angle, angle);
+  mp_ui->angle_le->setText (tl::to_qstring (tl::to_string (angle)));
+  lay::indicate_error (mp_ui->angle_le, 0);
+
+  bool mirror = false;
+  root->config_get (cfg_edit_inst_mirror, mirror);
+  mp_ui->mirror_cbx->setChecked (mirror);
+
+  double scale = 1.0;
+  root->config_get (cfg_edit_inst_scale, scale);
+  mp_ui->scale_le->setText (tl::to_qstring (tl::to_string (scale)));
+  lay::indicate_error (mp_ui->scale_le, 0);
+
+  //  array
+  bool array = false;
+  root->config_get (cfg_edit_inst_array, array);
+  mp_ui->array_grp->setChecked (array);
+
+  int rows = 1, columns = 1;
+  double row_x = 0.0, row_y = 0.0, column_x = 0.0, column_y = 0.0;
+  root->config_get (cfg_edit_inst_rows, rows);
+  root->config_get (cfg_edit_inst_row_x, row_x);
+  root->config_get (cfg_edit_inst_row_y, row_y);
+  root->config_get (cfg_edit_inst_columns, columns);
+  root->config_get (cfg_edit_inst_column_x, column_x);
+  root->config_get (cfg_edit_inst_column_y, column_y);
+
+  mp_ui->rows_le->setText (tl::to_qstring (tl::to_string (rows)));
+  lay::indicate_error (mp_ui->rows_le, 0);
+  mp_ui->row_x_le->setText (tl::to_qstring (tl::to_string (row_x)));
+  lay::indicate_error (mp_ui->row_x_le, 0);
+  mp_ui->row_y_le->setText (tl::to_qstring (tl::to_string (row_y)));
+  lay::indicate_error (mp_ui->row_y_le, 0);
+  mp_ui->columns_le->setText (tl::to_qstring (tl::to_string (columns)));
+  lay::indicate_error (mp_ui->columns_le, 0);
+  mp_ui->column_x_le->setText (tl::to_qstring (tl::to_string (column_x)));
+  lay::indicate_error (mp_ui->column_x_le, 0);
+  mp_ui->column_y_le->setText (tl::to_qstring (tl::to_string (column_y)));
+  lay::indicate_error (mp_ui->column_y_le, 0);
+
+  //  place origin of cell flag
+  bool place_origin = false;
+  root->config_get (cfg_edit_inst_place_origin, place_origin);
+  mp_ui->place_origin_cb->setChecked (place_origin);
+}
+
+// ------------------------------------------------------------------
+//  EditorOptionsInstPCellParam implementation
+
+EditorOptionsInstPCellParam::EditorOptionsInstPCellParam (lay::Dispatcher *dispatcher)
+  : lay::EditorOptionsPage (dispatcher), mp_pcell_parameters (0), mp_placeholder_label (0)
+{
+  mp_ui = new Ui::EditorOptionsInstPCellParam ();
+  mp_ui->setupUi (this);
+}
+
+EditorOptionsInstPCellParam::~EditorOptionsInstPCellParam ()
+{
+  delete mp_ui;
+  mp_ui = 0;
+}
+
+std::string
+EditorOptionsInstPCellParam::title () const
+{
+  return tl::to_string (QObject::tr ("PCell"));
+}
+
+void
+EditorOptionsInstPCellParam::apply (lay::Dispatcher *root)
+{
+  //  pcell parameters
+  std::string param;
+  db::Layout *layout = 0;
+
+  db::Library *lib = db::LibraryManager::instance ().lib_ptr_by_name (m_lib_name);
+  if (lib) {
+    layout = &lib->layout ();
+  } else if (m_cv_index >= 0 && lay::LayoutView::current () && lay::LayoutView::current ()->cellview (m_cv_index).is_valid ()) {
+    layout = &lay::LayoutView::current ()->cellview (m_cv_index)->layout ();
+  }
+
+  bool ok = true;
+
+  if (layout && mp_pcell_parameters) {
+    std::pair<bool, db::pcell_id_type> pc = layout->pcell_by_name (tl::to_string (m_cell_name).c_str ());
+    if (pc.first) {
+      const db::PCellDeclaration *pc_decl = layout->pcell_declaration (pc.second);
+      if (pc_decl) {
+        param = pcell_parameters_to_string (pc_decl->named_parameters (mp_pcell_parameters->get_parameters (&ok)));
+      }
+    }
+  }
+
+  if (ok) {
+    root->config_set (cfg_edit_inst_pcell_parameters, param);
+  }
+}
+
+void
+EditorOptionsInstPCellParam::setup (lay::Dispatcher *root)
+{
+  m_cv_index = -1;
+  if (lay::LayoutView::current ()) {
+    m_cv_index = lay::LayoutView::current ()->active_cellview_index ();
+  }
+
+  bool needs_update = (mp_pcell_parameters == 0);
+
   //  cell name
-  std::string s;
-  root->config_get (cfg_edit_inst_cell_name, s);
-  mp_ui->cell_le->setText (tl::to_qstring (s));
+  std::string cn;
+  root->config_get (cfg_edit_inst_cell_name, cn);
+  if (cn != m_cell_name) {
+    m_cell_name = cn;
+    needs_update = true;
+  }
 
   //  library
-  std::string l;
-  root->config_get (cfg_edit_inst_lib_name, l);
-  mp_ui->lib_cbx->set_current_library (db::LibraryManager::instance ().lib_ptr_by_name (l));
+  std::string ln;
+  root->config_get (cfg_edit_inst_lib_name, ln);
+  if (ln != m_lib_name) {
+    m_lib_name = ln;
+    needs_update = true;
+  }
+
+  db::Library *lib = db::LibraryManager::instance ().lib_ptr_by_name (m_lib_name);
 
   //  pcell parameters
   std::string param;
   root->config_get (cfg_edit_inst_pcell_parameters, param);
 
   db::Layout *layout = 0;
-  if (mp_ui->lib_cbx->current_library ()) {
-    layout = &mp_ui->lib_cbx->current_library ()->layout ();
+  if (lib) {
+    layout = &lib->layout ();
   } else if (m_cv_index >= 0 && lay::LayoutView::current () && lay::LayoutView::current ()->cellview (m_cv_index).is_valid ()) {
     layout = &lay::LayoutView::current ()->cellview (m_cv_index)->layout ();
   }
 
   std::vector<tl::Variant> pv;
 
-  if (layout && mp_pcell_parameters) {
+  if (layout) {
 
-    std::pair<bool, db::pcell_id_type> pc = layout->pcell_by_name (tl::to_string (mp_ui->cell_le->text ()).c_str ());
+    std::pair<bool, db::pcell_id_type> pc = layout->pcell_by_name (tl::to_string (m_cell_name).c_str ());
 
     if (pc.first) {
 
@@ -768,88 +795,49 @@ EditorOptionsInst::setup (lay::Plugin *root)
     }
 
   }
-  
+
+  if (! needs_update) {
+    bool ok = false;
+    if (mp_pcell_parameters->get_parameters (&ok) != pv || ! ok) {
+      needs_update = true;
+    }
+  }
+
   try {
-    update_pcell_parameters (pv);
+    if (needs_update) {
+      update_pcell_parameters (pv);
+    }
   } catch (...) { }
-
-  //  rotation, scaling
-  double angle = 0.0;
-  root->config_get (cfg_edit_inst_angle, angle);
-  mp_ui->angle_le->setText (tl::to_qstring (tl::to_string (angle)));
-
-  bool mirror = false;
-  root->config_get (cfg_edit_inst_mirror, mirror);
-  mp_ui->mirror_cbx->setChecked (mirror);
-
-  double scale = 1.0;
-  root->config_get (cfg_edit_inst_scale, scale);
-  mp_ui->scale_le->setText (tl::to_qstring (tl::to_string (scale)));
-
-  //  array
-  bool array = false;
-  root->config_get (cfg_edit_inst_array, array);
-  mp_ui->array_grp->setChecked (array);
-
-  int rows = 1, columns = 1;
-  double row_x = 0.0, row_y = 0.0, column_x = 0.0, column_y = 0.0;
-  root->config_get (cfg_edit_inst_rows, rows);
-  root->config_get (cfg_edit_inst_row_x, row_x);
-  root->config_get (cfg_edit_inst_row_y, row_y);
-  root->config_get (cfg_edit_inst_columns, columns);
-  root->config_get (cfg_edit_inst_column_x, column_x);
-  root->config_get (cfg_edit_inst_column_y, column_y);
-
-  mp_ui->rows_le->setText (tl::to_qstring (tl::to_string (rows)));
-  mp_ui->row_x_le->setText (tl::to_qstring (tl::to_string (row_x)));
-  mp_ui->row_y_le->setText (tl::to_qstring (tl::to_string (row_y)));
-  mp_ui->columns_le->setText (tl::to_qstring (tl::to_string (columns)));
-  mp_ui->column_x_le->setText (tl::to_qstring (tl::to_string (column_x)));
-  mp_ui->column_y_le->setText (tl::to_qstring (tl::to_string (column_y)));
-
-  //  place origin of cell flag
-  bool place_origin = false;
-  root->config_get (cfg_edit_inst_place_origin, place_origin);
-  mp_ui->place_origin_cb->setChecked (place_origin);
 }
 
-void  
-EditorOptionsInst::update_pcell_parameters ()
+void
+EditorOptionsInstPCellParam::update_pcell_parameters ()
 {
   update_pcell_parameters (std::vector <tl::Variant> ());
 }
 
-void  
-EditorOptionsInst::update_pcell_parameters (const std::vector <tl::Variant> &parameters)
+void
+EditorOptionsInstPCellParam::update_pcell_parameters (const std::vector <tl::Variant> &parameters)
 {
   db::Layout *layout = 0;
+  lay::LayoutView *view = lay::LayoutView::current ();
 
-  if (m_cv_index < 0 || !lay::LayoutView::current () || !lay::LayoutView::current ()->cellview (m_cv_index).is_valid ()) {
-    mp_ui->param_tab_widget->setTabEnabled (1, false);
-    return;
-  }
-
-  //  find the layout the cell has to be looked up: that is either the layout of the current instance or 
+  //  find the layout the cell has to be looked up: that is either the layout of the current instance or
   //  the library selected
-  if (mp_ui->lib_cbx->current_library ()) {
-    layout = &mp_ui->lib_cbx->current_library ()->layout ();
-  } else {
-    layout = &lay::LayoutView::current ()->cellview (m_cv_index)->layout ();
+  db::Library *lib = db::LibraryManager::instance ().lib_ptr_by_name (m_lib_name);
+  if (lib) {
+    layout = &lib->layout ();
+  } else if (view) {
+    const lay::CellView &cv = view->cellview (m_cv_index);
+    if (cv.is_valid ()) {
+      layout = &cv->layout ();
+    }
   }
 
-  std::pair<bool, db::pcell_id_type> pc = layout->pcell_by_name (tl::to_string (mp_ui->cell_le->text ()).c_str ());
-  std::pair<bool, db::cell_index_type> cc = layout->cell_by_name (tl::to_string (mp_ui->cell_le->text ()).c_str ());
-
-  //  by the way, update the foreground color of the cell edit box as well (red, if not valid)
-  QPalette pl = mp_ui->cell_le->palette ();
-  if (! pc.first && ! cc.first) {
-    pl.setColor (QPalette::Text, Qt::red);
-    pl.setColor (QPalette::Base, QColor (Qt::red).lighter (180));
-  } else {
-    pl.setColor (QPalette::Text, palette ().color (QPalette::Text));
-    pl.setColor (QPalette::Base, palette ().color (QPalette::Base));
+  std::pair<bool, db::pcell_id_type> pc (false, 0);
+  if (layout) {
+    pc = layout->pcell_by_name (tl::to_string (m_cell_name).c_str ());
   }
-  mp_ui->cell_le->setPalette (pl);
 
   PCellParametersPage::State pcp_state;
 
@@ -860,19 +848,30 @@ EditorOptionsInst::update_pcell_parameters (const std::vector <tl::Variant> &par
     mp_pcell_parameters->deleteLater ();
   }
 
+  if (mp_placeholder_label) {
+    mp_placeholder_label->hide ();
+    mp_placeholder_label->deleteLater ();
+  }
+
   mp_pcell_parameters = 0;
+  mp_placeholder_label = 0;
 
-  if (pc.first && layout->pcell_declaration (pc.second)) {
+  if (pc.first && layout->pcell_declaration (pc.second) && view && view->cellview (m_cv_index).is_valid ()) {
 
-    mp_ui->param_tab_widget->setTabEnabled (1, true);
-    lay::LayoutView *view = lay::LayoutView::current ();
-    mp_pcell_parameters = new PCellParametersPage (mp_ui->pcell_tab, &view->cellview (m_cv_index)->layout (), view, m_cv_index, layout->pcell_declaration (pc.second), parameters);
-    mp_ui->pcell_tab->layout ()->addWidget (mp_pcell_parameters);
+    mp_pcell_parameters = new PCellParametersPage (this, true /*dense*/);
+    mp_pcell_parameters->setup (&view->cellview (m_cv_index)->layout (), view, m_cv_index, layout->pcell_declaration (pc.second), parameters);
+    this->layout ()->addWidget (mp_pcell_parameters);
 
     mp_pcell_parameters->set_state (pcp_state);
+    connect (mp_pcell_parameters, SIGNAL (edited ()), this, SLOT (edited ()));
 
   } else {
-    mp_ui->param_tab_widget->setTabEnabled (1, false);
+
+    mp_placeholder_label = new QLabel (this);
+    mp_placeholder_label->setText (tr ("Not a PCell"));
+    mp_placeholder_label->setAlignment (Qt::AlignHCenter | Qt::AlignVCenter);
+    this->layout ()->addWidget (mp_placeholder_label);
+
   }
 }
 
diff --git a/src/edt/edt/edtEditorOptionsPages.h b/src/edt/edt/edtEditorOptionsPages.h
index 65145212f..3b639c5d8 100644
--- a/src/edt/edt/edtEditorOptionsPages.h
+++ b/src/edt/edt/edtEditorOptionsPages.h
@@ -24,12 +24,17 @@
 #ifndef HDR_edtEditorOptionsPages
 #define HDR_edtEditorOptionsPages
 
+#include "layEditorOptionsPage.h"
+
 #include <tlVariant.h>
 
-#include <QDialog>
+#include <QFrame>
 #include <vector>
 #include <string>
 
+class QTabWidget;
+class QLabel;
+
 namespace Ui
 {
   class EditorOptionsDialog;
@@ -39,6 +44,7 @@ namespace Ui
   class EditorOptionsPath;
   class EditorOptionsText;
   class EditorOptionsInst;
+  class EditorOptionsInstPCellParam;
 }
 
 namespace lay
@@ -53,83 +59,22 @@ namespace edt
 
 class PCellParametersPage;
 
-class EditorOptionsPages;
-
-/**
- *  @brief The base class for a object properties page 
- */
-class EditorOptionsPage
-{
-public:
-  EditorOptionsPage ();
-  virtual ~EditorOptionsPage ();
-
-  virtual QWidget *q_frame () = 0;
-  virtual std::string title () const = 0;
-  virtual int order () const = 0;
-  virtual void apply (lay::Plugin *root) = 0;
-  virtual void setup (lay::Plugin *root) = 0;
-
-  bool active () const { return m_active; }
-  void activate (bool active);
-  void set_owner (EditorOptionsPages *owner);
-
-  const lay::PluginDeclaration *plugin_declaration () const { return mp_plugin_declaration; }
-  void set_plugin_declaration (const lay::PluginDeclaration *pd) { mp_plugin_declaration = pd; }
-
-private:
-  EditorOptionsPages *mp_owner;
-  bool m_active;
-  const lay::PluginDeclaration *mp_plugin_declaration;
-};
-
-/**
- *  @brief The object properties dialog
- */
-class EditorOptionsPages
-  : public QDialog
-{
-Q_OBJECT
-
-public:
-  EditorOptionsPages (const std::vector<edt::EditorOptionsPage *> &pages, lay::Dispatcher *root);
-  ~EditorOptionsPages ();
-
-  void unregister_page (edt::EditorOptionsPage *page);
-  void activate_page (edt::EditorOptionsPage *page);
-
-public slots:
-  void apply ();
-  void setup ();
-  void accept ();
-
-private:
-  std::vector <edt::EditorOptionsPage *> m_pages;
-  Ui::EditorOptionsDialog *mp_ui;
-  lay::Dispatcher *mp_root;
-
-  void update (edt::EditorOptionsPage *page);
-  void do_apply ();
-};
-
 /**
  *  @brief The generic properties page
  */
 class EditorOptionsGeneric
-  : public QWidget, public EditorOptionsPage
+  : public lay::EditorOptionsPage
 {
 Q_OBJECT
 
 public:
-  EditorOptionsGeneric ();
+  EditorOptionsGeneric (lay::Dispatcher *dispatcher);
   ~EditorOptionsGeneric ();
 
-  virtual QWidget *q_frame () { return this; }
-
   virtual std::string title () const;
   virtual int order () const { return 0; }
-  void apply (lay::Plugin *root);
-  void setup (lay::Plugin *root);
+  void apply (lay::Dispatcher *root);
+  void setup (lay::Dispatcher *root);
 
 public slots:
   void grid_changed (int);
@@ -143,18 +88,16 @@ private:
  *  @brief The text properties page
  */
 class EditorOptionsText
-  : public QWidget, public EditorOptionsPage 
+  : public lay::EditorOptionsPage
 {
 public:
-  EditorOptionsText ();
+  EditorOptionsText (lay::Dispatcher *dispatcher);
   ~EditorOptionsText ();
 
-  virtual QWidget *q_frame () { return this; }
-
   virtual std::string title () const;
   virtual int order () const { return 10; }
-  void apply (lay::Plugin *root);
-  void setup (lay::Plugin *root);
+  void apply (lay::Dispatcher *root);
+  void setup (lay::Dispatcher *root);
 
 private:
   Ui::EditorOptionsText *mp_ui;
@@ -164,20 +107,18 @@ private:
  *  @brief The path properties page
  */
 class EditorOptionsPath
-  : public QWidget, public EditorOptionsPage 
+  : public lay::EditorOptionsPage
 {
 Q_OBJECT 
 
 public:
-  EditorOptionsPath ();
+  EditorOptionsPath (lay::Dispatcher *dispatcher);
   ~EditorOptionsPath ();
 
-  virtual QWidget *q_frame () { return this; }
-
   virtual std::string title () const;
-  virtual int order () const { return 20; }
-  void apply (lay::Plugin *root);
-  void setup (lay::Plugin *root);
+  virtual int order () const { return 30; }
+  void apply (lay::Dispatcher *root);
+  void setup (lay::Dispatcher *root);
 
 public slots:
   void type_changed (int);
@@ -190,7 +131,7 @@ private:
  *  @brief The instance properties page
  */
 class EditorOptionsInst
-  : public QWidget, public EditorOptionsPage 
+  : public lay::EditorOptionsPage
 {
 Q_OBJECT 
 
@@ -198,25 +139,49 @@ public:
   EditorOptionsInst (lay::Dispatcher *root);
   ~EditorOptionsInst ();
 
-  virtual QWidget *q_frame () { return this; }
-
   virtual std::string title () const;
   virtual int order () const { return 20; }
-  void apply (lay::Plugin *root);
-  void setup (lay::Plugin *root);
+  void apply (lay::Dispatcher *root);
+  void setup (lay::Dispatcher *root);
 
-public slots:
+private slots:
   void array_changed ();
   void browse_cell ();
-  void update_pcell_parameters ();
-  void library_changed (int index);
-  void cell_name_changed (const QString &s);
+  void library_changed ();
+  void update_cell_edits ();
 
 private:
   Ui::EditorOptionsInst *mp_ui;
-  lay::Dispatcher *mp_root;
   edt::PCellParametersPage *mp_pcell_parameters;
   int m_cv_index;
+};
+
+/**
+ *  @brief The instance properties page (PCell parameters)
+ */
+class EditorOptionsInstPCellParam
+  : public lay::EditorOptionsPage
+{
+Q_OBJECT
+
+public:
+  EditorOptionsInstPCellParam (lay::Dispatcher *root);
+  ~EditorOptionsInstPCellParam ();
+
+  virtual std::string title () const;
+  virtual int order () const { return 21; }
+  void apply (lay::Dispatcher *root);
+  void setup (lay::Dispatcher *root);
+
+private slots:
+  void update_pcell_parameters ();
+
+private:
+  Ui::EditorOptionsInstPCellParam *mp_ui;
+  edt::PCellParametersPage *mp_pcell_parameters;
+  QLabel *mp_placeholder_label;
+  int m_cv_index;
+  std::string m_lib_name, m_cell_name;
 
   void update_pcell_parameters (const std::vector <tl::Variant> &parameters);
 };
diff --git a/src/edt/edt/edtInstPropertiesPage.cc b/src/edt/edt/edtInstPropertiesPage.cc
index 6f62c5654..5266ff485 100644
--- a/src/edt/edt/edtInstPropertiesPage.cc
+++ b/src/edt/edt/edtInstPropertiesPage.cc
@@ -31,6 +31,7 @@
 #include "layObjectInstPath.h"
 #include "layLayoutView.h"
 #include "layCellSelectionForm.h"
+#include "layQtTools.h"
 #include "tlExceptions.h"
 #include "tlString.h"
 
@@ -65,6 +66,43 @@ InstPropertiesPage::InstPropertiesPage (edt::Service *service, db::Manager *mana
   connect (lib_cbx, SIGNAL (currentIndexChanged (int)), this, SLOT (library_changed (int)));
   connect (cell_name_le, SIGNAL (textChanged (const QString &)), this, SLOT (cell_name_changed (const QString &)));
 
+  if (! readonly ()) {
+
+    connect (lib_cbx, SIGNAL (activated (int)), this, SIGNAL (edited ()));
+    connect (cell_name_le, SIGNAL (editingFinished ()), this, SIGNAL (edited ()));
+    connect (array_grp, SIGNAL (clicked ()), this, SIGNAL (edited ()));
+    connect (rows_le, SIGNAL (editingFinished ()), this, SIGNAL (edited ()));
+    connect (columns_le, SIGNAL (editingFinished ()), this, SIGNAL (edited ()));
+    connect (row_x_le, SIGNAL (editingFinished ()), this, SIGNAL (edited ()));
+    connect (row_y_le, SIGNAL (editingFinished ()), this, SIGNAL (edited ()));
+    connect (column_x_le, SIGNAL (editingFinished ()), this, SIGNAL (edited ()));
+    connect (column_y_le, SIGNAL (editingFinished ()), this, SIGNAL (edited ()));
+    connect (pos_x_le, SIGNAL (editingFinished ()), this, SIGNAL (edited ()));
+    connect (pos_y_le, SIGNAL (editingFinished ()), this, SIGNAL (edited ()));
+    connect (angle_le, SIGNAL (editingFinished ()), this, SIGNAL (edited ()));
+    connect (mag_le, SIGNAL (editingFinished ()), this, SIGNAL (edited ()));
+    connect (mirror_cbx, SIGNAL (clicked ()), this, SIGNAL (edited ()));
+
+  } else {
+
+    browse_pb->setEnabled (false);
+    cell_name_le->setReadOnly (true);
+    rows_le->setReadOnly (true);
+    columns_le->setReadOnly (true);
+    row_x_le->setReadOnly (true);
+    row_y_le->setReadOnly (true);
+    column_x_le->setReadOnly (true);
+    column_y_le->setReadOnly (true);
+    pos_x_le->setReadOnly (true);
+    pos_y_le->setReadOnly (true);
+    angle_le->setReadOnly (true);
+    mag_le->setReadOnly (true);
+    lib_cbx->setEnabled (false);
+    array_grp->setEnabled (false);
+    mirror_cbx->setEnabled (false);
+
+  }
+
   QHBoxLayout *layout = new QHBoxLayout (pcell_tab);
   layout->setMargin (0);
   pcell_tab->setLayout (layout);
@@ -125,12 +163,19 @@ BEGIN_PROTECTED
   }
 
   if (form.exec ()) {
+
+    cell_name_le->blockSignals (true);
     if (form.selected_cell_is_pcell ()) {
       cell_name_le->setText (tl::to_qstring (layout->pcell_header (form.selected_pcell_id ())->get_name ()));
     } else if (layout->is_valid_cell_index (form.selected_cell_index ())) {
       cell_name_le->setText (tl::to_qstring (layout->cell_name (form.selected_cell_index ())));
     }
+    cell_name_le->blockSignals (false);
+
     update_pcell_parameters ();
+
+    emit edited ();
+
   }
 
 END_PROTECTED
@@ -140,7 +185,9 @@ void
 InstPropertiesPage::show_props ()
 {
   lay::UserPropertiesForm props_form (this);
-  props_form.show (mp_service->view (), m_selection_ptrs [m_index]->cv_index (), m_prop_id);
+  if (props_form.show (mp_service->view (), m_selection_ptrs [m_index]->cv_index (), m_prop_id)) {
+    emit edited ();
+  }
 }
 
 void
@@ -222,6 +269,7 @@ InstPropertiesPage::update ()
   db::cell_index_type def_cell_index = pos->back ().inst_ptr.cell_index ();
   const db::Cell &def_cell = def_layout->cell (def_cell_index);
 
+  lib_cbx->blockSignals (true);
   std::pair<db::Library *, db::cell_index_type> dl = def_layout->defining_library (def_cell_index);
   lib_cbx->set_technology_filter (cv->tech_name (), true);
   lib_cbx->set_current_library (dl.first);
@@ -229,13 +277,16 @@ InstPropertiesPage::update ()
     def_layout = &dl.first->layout ();
     def_cell_index = dl.second;
   }
+  lib_cbx->blockSignals (false);
 
   std::pair<bool, db::pcell_id_type> pci = def_layout->is_pcell_instance (def_cell_index);
+  cell_name_le->blockSignals (true);
   if (pci.first && def_layout->pcell_declaration (pci.second)) {
     cell_name_le->setText (tl::to_qstring (def_layout->pcell_header (pci.second)->get_name ()));
   } else {
     cell_name_le->setText (tl::to_qstring (def_layout->cell_name (def_cell_index)));
   }
+  cell_name_le->blockSignals (false);
 
   db::Vector rowv, columnv;
   unsigned long rows, columns;
@@ -325,6 +376,9 @@ InstPropertiesPage::readonly ()
 ChangeApplicator *
 InstPropertiesPage::create_applicator (db::Cell & /*cell*/, const db::Instance & /*inst*/, double dbu)
 {
+  bool has_error = false;
+  bool has_pcell_error = false;
+
   std::auto_ptr<CombinedChangeApplicator> appl (new CombinedChangeApplicator ());
 
   edt::Service::obj_iterator pos = m_selection_ptrs [m_index];
@@ -343,34 +397,69 @@ InstPropertiesPage::create_applicator (db::Cell & /*cell*/, const db::Instance &
     layout = &cv->layout ();
   }
 
-  std::pair<bool, db::cell_index_type> ci = layout->cell_by_name (tl::to_string (cell_name_le->text ()).c_str ());
-  std::pair<bool, db::pcell_id_type> pci = layout->pcell_by_name (tl::to_string (cell_name_le->text ()).c_str ());
-  if (! ci.first && ! pci.first) {
-    throw tl::Exception (tl::to_string (QObject::tr ("Not a valid cell name: %s")).c_str (), tl::to_string (cell_name_le->text ()).c_str ());
+  try {
+
+    std::pair<bool, db::cell_index_type> ci = layout->cell_by_name (tl::to_string (cell_name_le->text ()).c_str ());
+    std::pair<bool, db::pcell_id_type> pci = layout->pcell_by_name (tl::to_string (cell_name_le->text ()).c_str ());
+    if (! ci.first && ! pci.first) {
+      throw tl::Exception (tl::to_string (QObject::tr ("Not a valid cell or PCell name: %s")).c_str (), tl::to_string (cell_name_le->text ()).c_str ());
+    }
+
+    lay::indicate_error (cell_name_le, 0);
+
+  } catch (tl::Exception &ex) {
+    lay::indicate_error (cell_name_le, &ex);
+    has_error = true;
   }
 
-  db::cell_index_type inst_cell_index = ci.second;
+  try {
 
-  //  instantiate the PCell
-  if (pci.first) {
-    tl_assert (mp_pcell_parameters != 0);
-    tl_assert (layout->pcell_declaration (pci.second) == mp_pcell_parameters->pcell_decl ());
-    inst_cell_index = layout->get_pcell_variant (pci.second, mp_pcell_parameters->get_parameters ());
-  }
+    std::pair<bool, db::cell_index_type> ci = layout->cell_by_name (tl::to_string (cell_name_le->text ()).c_str ());
+    std::pair<bool, db::pcell_id_type> pci = layout->pcell_by_name (tl::to_string (cell_name_le->text ()).c_str ());
+    tl_assert (ci.first || pci.first);
 
-  //  reference the library
-  if (lib) {
-    layout = & cv->layout ();
-    inst_cell_index = layout->get_lib_proxy (lib, inst_cell_index);
-  }
+    db::cell_index_type inst_cell_index = 0;
 
-  if (inst_cell_index != pos->back ().inst_ptr.cell_index ()) {
-    appl->add (new ChangeTargetCellApplicator (inst_cell_index));
+    //  instantiate the PCell
+    if (pci.first) {
+      tl_assert (mp_pcell_parameters != 0);
+      tl_assert (layout->pcell_declaration (pci.second) == mp_pcell_parameters->pcell_decl ());
+      inst_cell_index = layout->get_pcell_variant (pci.second, mp_pcell_parameters->get_parameters ());
+    } else {
+      inst_cell_index = ci.second;
+    }
+
+    //  reference the library
+    if (lib) {
+      layout = & cv->layout ();
+      inst_cell_index = layout->get_lib_proxy (lib, inst_cell_index);
+    }
+
+    if (inst_cell_index != pos->back ().inst_ptr.cell_index ()) {
+      appl->add (new ChangeTargetCellApplicator (inst_cell_index));
+    }
+
+  } catch (tl::Exception &ex) {
+    has_pcell_error = true;
   }
 
   double x = 0.0, y = 0.0;
-  tl::from_string (tl::to_string (pos_x_le->text ()), x);
-  tl::from_string (tl::to_string (pos_y_le->text ()), y);
+
+  try {
+    tl::from_string (tl::to_string (pos_x_le->text ()), x);
+    lay::indicate_error (pos_x_le, 0);
+  } catch (tl::Exception &ex) {
+    lay::indicate_error (pos_x_le, &ex);
+    has_error = true;
+  }
+
+  try {
+    tl::from_string (tl::to_string (pos_y_le->text ()), y);
+    lay::indicate_error (pos_y_le, 0);
+  } catch (tl::Exception &ex) {
+    lay::indicate_error (pos_y_le, &ex);
+    has_error = true;
+  }
 
   db::DCplxTrans t;
   if (abs_cb->isChecked ()) {
@@ -381,20 +470,32 @@ InstPropertiesPage::create_applicator (db::Cell & /*cell*/, const db::Instance &
 
   bool mirror = mirror_cbx->isChecked ();
   double angle = 0.0;
-  tl::from_string (tl::to_string (angle_le->text ()), angle);
+  try {
+    tl::from_string (tl::to_string (angle_le->text ()), angle);
+    lay::indicate_error (angle_le, 0);
+  } catch (tl::Exception &ex) {
+    lay::indicate_error (angle_le, &ex);
+    has_error = true;
+  }
 
   double mag = 0.0;
-  tl::from_string (tl::to_string (mag_le->text ()), mag);
+  try {
+    tl::from_string (tl::to_string (mag_le->text ()), mag);
+    lay::indicate_error (mag_le, 0);
+  } catch (tl::Exception &ex) {
+    lay::indicate_error (mag_le, &ex);
+    has_error = true;
+  }
 
   angle -= (floor (angle / 360.0) + 1.0) * 360.0;
   while (angle < -1e-6) {
     angle += 360.0;
   }
 
-  db::CellInstArray::complex_trans_type tr = pos->back ().inst_ptr.complex_trans ();
+  db::CellInstArray::complex_trans_type trans = pos->back ().inst_ptr.complex_trans ();
 
-  if (fabs (angle - tr.angle ()) > 1e-6 || mirror != tr.is_mirror () || fabs (mag - tr.mag ()) > 1e-6 || ! disp.equal (tr.disp () * dbu)) {
-    appl->add (new ChangeInstanceTransApplicator (angle, tr.angle (), mirror, tr.is_mirror (), mag, tr.mag (), disp, tr.disp () * dbu));
+  if (fabs (angle - trans.angle ()) > 1e-6 || mirror != trans.is_mirror () || fabs (mag - trans.mag ()) > 1e-6 || ! disp.equal (trans.disp () * dbu)) {
+    appl->add (new ChangeInstanceTransApplicator (angle, trans.angle (), mirror, trans.is_mirror (), mag, trans.mag (), disp, trans.disp () * dbu));
   }
 
   db::CellInstArray::vector_type a_org, b_org;
@@ -407,12 +508,53 @@ InstPropertiesPage::create_applicator (db::Cell & /*cell*/, const db::Instance &
     double rx = 0.0, ry = 0.0;
     unsigned long rows = 0, cols = 0;
 
-    tl::from_string (tl::to_string (column_x_le->text ()), cx);
-    tl::from_string (tl::to_string (column_y_le->text ()), cy);
-    tl::from_string (tl::to_string (row_x_le->text ()), rx);
-    tl::from_string (tl::to_string (row_y_le->text ()), ry);
-    tl::from_string (tl::to_string (rows_le->text ()), rows);
-    tl::from_string (tl::to_string (columns_le->text ()), cols);
+    try {
+      tl::from_string (tl::to_string (column_x_le->text ()), cx);
+      lay::indicate_error (column_x_le, 0);
+    } catch (tl::Exception &ex) {
+      lay::indicate_error (column_x_le, &ex);
+      has_error = true;
+    }
+
+    try {
+      tl::from_string (tl::to_string (column_y_le->text ()), cy);
+      lay::indicate_error (column_y_le, 0);
+    } catch (tl::Exception &ex) {
+      lay::indicate_error (column_y_le, &ex);
+      has_error = true;
+    }
+
+    try {
+      tl::from_string (tl::to_string (row_x_le->text ()), rx);
+      lay::indicate_error (row_x_le, 0);
+    } catch (tl::Exception &ex) {
+      lay::indicate_error (row_x_le, &ex);
+      has_error = true;
+    }
+
+    try {
+      tl::from_string (tl::to_string (row_y_le->text ()), ry);
+      lay::indicate_error (row_y_le, 0);
+    } catch (tl::Exception &ex) {
+      lay::indicate_error (row_y_le, &ex);
+      has_error = true;
+    }
+
+    try {
+      tl::from_string (tl::to_string (rows_le->text ()), rows);
+      lay::indicate_error (rows_le, 0);
+    } catch (tl::Exception &ex) {
+      lay::indicate_error (rows_le, &ex);
+      has_error = true;
+    }
+
+    try {
+      tl::from_string (tl::to_string (columns_le->text ()), cols);
+      lay::indicate_error (columns_le, 0);
+    } catch (tl::Exception &ex) {
+      lay::indicate_error (columns_le, &ex);
+      has_error = true;
+    }
 
     db::DVector rv = db::DVector (dpoint_from_dpoint (db::DPoint (rx, ry), dbu, du, t));
     db::DVector cv = db::DVector (dpoint_from_dpoint (db::DPoint (cx, cy), dbu, du, t));
@@ -432,6 +574,14 @@ InstPropertiesPage::create_applicator (db::Cell & /*cell*/, const db::Instance &
 
   }
 
+  if (has_error || has_pcell_error) {
+    throw tl::Exception (tl::to_string (tr ("At least one value and PCell parameter is not correct - see hightlighted entry fields or the PCell error indicator")));
+  } else if (has_error) {
+    throw tl::Exception (tl::to_string (tr ("At least one value is not correct - see hightlighted entry fields")));
+  } else if (has_pcell_error) {
+    throw tl::Exception (tl::to_string (tr ("At least one PCell parameter is not correct - see hightlighted entry fields or the PCell error indicator")));
+  }
+
   return appl.release ();
 }
 
@@ -453,7 +603,7 @@ InstPropertiesPage::recompute_selection_ptrs (const std::vector<lay::ObjectInstP
 }
 
 void 
-InstPropertiesPage::do_apply (bool current_only)
+InstPropertiesPage::do_apply (bool current_only, bool relative)
 {
   lay::LayerState layer_state = mp_service->view ()->layer_snapshot ();
   unsigned int cv_index = m_selection_ptrs [m_index]->cv_index ();
@@ -482,32 +632,7 @@ InstPropertiesPage::do_apply (bool current_only)
 
   bool relative_mode = false;
   if (! current_only && applicator->supports_relative_mode ()) {
-
-    static bool s_relative_mode = true;
-
-    QMessageBox mb (QMessageBox::Question, 
-                    tr ("Apply Changes To All"), 
-                    tr ("For this operation absolute or relative mode is available which affects the way parameters of the selected objects are changed:\n\n"
-                        "In absolute mode, they will be set to the given value. In relative mode, they will be adjusted by the same amount.\n"),
-                    QMessageBox::NoButton, this);
-
-    mb.addButton (tr ("Cancel"), QMessageBox::RejectRole);
-    QPushButton *absolute = mb.addButton (tr ("Absolute"), QMessageBox::NoRole);
-    QPushButton *relative = mb.addButton (tr ("Relative"), QMessageBox::YesRole);
-    
-    mb.setDefaultButton (s_relative_mode ? relative : absolute);
-
-    mb.exec ();
-
-    if (mb.clickedButton () == absolute) {
-      s_relative_mode = relative_mode = false;
-    } else if (mb.clickedButton () == relative) {
-      s_relative_mode = relative_mode = true;
-    } else {
-      //  Cancel pressed
-      return;
-    }
-
+    relative_mode = relative;
   }
 
   //  Note: using the apply-all scheme for applying a single change may look like overhead.
@@ -599,7 +724,7 @@ InstPropertiesPage::do_apply (bool current_only)
 void 
 InstPropertiesPage::apply ()
 {
-  do_apply (true);
+  do_apply (true, false);
 }
 
 bool
@@ -609,9 +734,9 @@ InstPropertiesPage::can_apply_to_all () const
 }
 
 void 
-InstPropertiesPage::apply_to_all ()
+InstPropertiesPage::apply_to_all (bool relative)
 {
-  do_apply (false);
+  do_apply (false, relative);
 }
 
 void
@@ -636,16 +761,13 @@ InstPropertiesPage::update_pcell_parameters ()
   std::pair<bool, db::pcell_id_type> pc = layout->pcell_by_name (tl::to_string (cell_name_le->text ()).c_str ());
   std::pair<bool, db::cell_index_type> cc = layout->cell_by_name (tl::to_string (cell_name_le->text ()).c_str ());
 
-  //  by the way, update the foreground color of the cell edit box as well (red, if not valid)
-  QPalette pl = cell_name_le->palette ();
+  //  indicate an invalid cell name
   if (! pc.first && ! cc.first) {
-    pl.setColor (QPalette::Text, Qt::red);
-    pl.setColor (QPalette::Base, QColor (Qt::red).lighter (180));
+    tl::Exception ex (tl::to_string (QObject::tr ("Not a valid cell or PCell name: %s")).c_str (), tl::to_string (cell_name_le->text ()).c_str ());
+    lay::indicate_error (cell_name_le, &ex);
   } else {
-    pl.setColor (QPalette::Text, palette ().color (QPalette::Text));
-    pl.setColor (QPalette::Base, palette ().color (QPalette::Base));
+    lay::indicate_error (cell_name_le, 0);
   }
-  cell_name_le->setPalette (pl);
 
   if (pc.first && layout->pcell_declaration (pc.second)) {
 
@@ -686,13 +808,14 @@ InstPropertiesPage::update_pcell_parameters ()
         mp_pcell_parameters->deleteLater ();
       }
 
-      mp_pcell_parameters = new PCellParametersPage (pcell_tab, &cv->layout (), mp_service->view (), pos->cv_index (), layout->pcell_declaration (pc.second), parameters);
+      mp_pcell_parameters = new PCellParametersPage (pcell_tab);
+      connect (mp_pcell_parameters, SIGNAL (edited ()), this, SIGNAL (edited ()));
+      mp_pcell_parameters->setup (&cv->layout (), mp_service->view (), pos->cv_index (), layout->pcell_declaration (pc.second), parameters);
       pcell_tab->layout ()->addWidget (mp_pcell_parameters);
 
     }
 
     param_tab_widget->setTabEnabled (1, true);
-    param_tab_widget->setCurrentIndex (1);
 
   } else {
 
@@ -704,8 +827,11 @@ InstPropertiesPage::update_pcell_parameters ()
 
     mp_pcell_parameters = 0;
 
-    param_tab_widget->setCurrentIndex (0);
+    if (param_tab_widget->currentIndex () == 1) {
+      param_tab_widget->setCurrentIndex (0);
+    }
     param_tab_widget->setTabEnabled (1, false);
+
   }
 
 }
diff --git a/src/edt/edt/edtInstPropertiesPage.h b/src/edt/edt/edtInstPropertiesPage.h
index f648482dc..28394f4b3 100644
--- a/src/edt/edt/edtInstPropertiesPage.h
+++ b/src/edt/edt/edtInstPropertiesPage.h
@@ -68,9 +68,9 @@ protected:
 
   virtual bool readonly ();
   virtual void apply (); 
-  virtual void apply_to_all ();
+  virtual void apply_to_all (bool relative);
   virtual bool can_apply_to_all () const;
-  void do_apply (bool current_only);
+  void do_apply (bool current_only, bool relative);
   virtual ChangeApplicator *create_applicator (db::Cell &cell, const db::Instance &inst, double dbu);
 
 protected slots:
diff --git a/src/edt/edt/edtMainService.cc b/src/edt/edt/edtMainService.cc
index a5068438c..29984d719 100644
--- a/src/edt/edt/edtMainService.cc
+++ b/src/edt/edt/edtMainService.cc
@@ -30,7 +30,11 @@
 #include "tlExceptions.h"
 #include "layLayoutView.h"
 #include "layDialogs.h"
+#include "laySelector.h"
 #include "layCellSelectionForm.h"
+#include "layFinder.h"
+#include "layLayerProperties.h"
+#include "layLayerTreeModel.h"
 #include "tlProgress.h"
 #include "edtPlugin.h"
 #include "edtMainService.h"
@@ -39,8 +43,11 @@
 #include "edtConfig.h"
 #include "edtDialogs.h"
 #include "edtEditorOptionsPages.h"
+#include "edtDistribute.h"
 
 #include <QMessageBox>
+#include <QFontInfo>
+#include <QWidgetAction>
 
 namespace edt
 {
@@ -58,12 +65,18 @@ MainService::MainService (db::Manager *manager, lay::LayoutView *view, lay::Disp
     m_flatten_insts_levels (std::numeric_limits<int>::max ()),
     m_flatten_prune (false),
     m_align_hmode (0), m_align_vmode (0), m_align_visible_layers (false),
+    m_hdistribute (true),
+    m_distribute_hmode (1), m_distribute_hpitch (0.0), m_distribute_hspace (0.0),
+    m_vdistribute (true),
+    m_distribute_vmode (1), m_distribute_vpitch (0.0), m_distribute_vspace (0.0),
+    m_distribute_visible_layers (false),
     m_origin_mode_x (-1), m_origin_mode_y (-1), m_origin_visible_layers_for_bbox (false),
     m_array_a (0.0, 1.0), m_array_b (1.0, 0.0),
     m_array_na (1), m_array_nb (1),
     m_router (0.0), m_rinner (0.0), m_npoints (64), m_undo_before_apply (true),
     mp_round_corners_dialog (0),
     mp_align_options_dialog (0),
+    mp_distribute_options_dialog (0),
     mp_flatten_inst_options_dialog (0),
     mp_make_cell_options_dialog (0),
     mp_make_array_options_dialog (0)
@@ -94,6 +107,15 @@ MainService::align_options_dialog ()
   return mp_align_options_dialog;
 }
 
+edt::DistributeOptionsDialog *
+MainService::distribute_options_dialog ()
+{
+  if (! mp_distribute_options_dialog) {
+    mp_distribute_options_dialog = new edt::DistributeOptionsDialog (view ());
+  }
+  return mp_distribute_options_dialog;
+}
+
 lay::FlattenInstOptionsDialog *
 MainService::flatten_inst_options_dialog ()
 {
@@ -128,10 +150,10 @@ MainService::menu_activated (const std::string &symbol)
     cm_descend ();
   } else if (symbol == "edt::ascend") {
     cm_ascend ();
-  } else if (symbol == "edt::edit_options") {
-    cm_edit_options ();
   } else if (symbol == "edt::sel_align") {
     cm_align ();
+  } else if (symbol == "edt::sel_distribute") {
+    cm_distribute ();
   } else if (symbol == "edt::sel_tap") {
     cm_tap ();
   } else if (symbol == "edt::sel_round_corners") {
@@ -1835,7 +1857,115 @@ MainService::cm_align ()
   }
 }
 
-void 
+void
+MainService::cm_distribute ()
+{
+  tl_assert (view ()->is_editable ());
+  check_no_guiding_shapes ();
+
+  std::vector<edt::Service *> edt_services = view ()->get_plugins <edt::Service> ();
+
+  if (! distribute_options_dialog ()->exec_dialog (view (), m_hdistribute, m_distribute_hmode, m_distribute_hpitch, m_distribute_hspace,
+                                                            m_vdistribute, m_distribute_vmode, m_distribute_vpitch, m_distribute_vspace,
+                                                            m_distribute_visible_layers)) {
+    return;
+  }
+
+  if (! m_hdistribute && ! m_vdistribute) {
+    return;
+  }
+
+  //  count the items
+  size_t n = 0;
+  for (std::vector<edt::Service *>::const_iterator es = edt_services.begin (); es != edt_services.end (); ++es) {
+    for (edt::Service::obj_iterator s = (*es)->selection ().begin (); s != (*es)->selection ().end (); ++s) {
+      ++n;
+    }
+  }
+
+  std::vector<std::pair<size_t, size_t> > objects_for_service;
+  std::vector<db::DCplxTrans> transformations;
+
+  {
+
+    std::vector<db::DBox> org_boxes;
+    org_boxes.reserve (n);
+
+    edt::distributed_placer<db::DBox, size_t> placer;
+    placer.reserve (n);
+
+    size_t i = 0;
+
+    for (std::vector<edt::Service *>::const_iterator es = edt_services.begin (); es != edt_services.end (); ++es) {
+
+      objects_for_service.push_back (std::make_pair (i, i));
+
+      for (edt::Service::obj_iterator s = (*es)->selection ().begin (); s != (*es)->selection ().end (); ++s) {
+
+        const db::Layout &layout = view ()->cellview (s->cv_index ())->layout ();
+        db::CplxTrans tr = db::CplxTrans (layout.dbu ()) * s->trans ();
+
+        db::DBox box;
+        if (! s->is_cell_inst ()) {
+          box = tr * s->shape ().bbox ();
+        } else {
+          box = inst_bbox (tr, view (), s->cv_index (), s->back (), m_distribute_visible_layers);
+        }
+
+        org_boxes.push_back (box);
+        placer.insert (box, i);
+
+        ++i;
+
+      }
+
+      objects_for_service.back ().second = i;
+
+    }
+
+    int href = int (m_distribute_hmode - 2);
+    int vref = 2 - int (m_distribute_vmode);
+
+    if (m_hdistribute && m_vdistribute) {
+      placer.distribute_matrix (href, m_distribute_hpitch, m_distribute_hspace,
+                                vref, m_distribute_vpitch, m_distribute_vspace);
+    } else if (m_hdistribute) {
+      placer.distribute_h (href, vref, m_distribute_hpitch, m_distribute_hspace);
+    } else if (m_vdistribute) {
+      placer.distribute_v (vref, href, m_distribute_vpitch, m_distribute_vspace);
+    }
+
+    transformations.resize (org_boxes.size ());
+
+    for (edt::distributed_placer<db::DBox, size_t>::iterator i = placer.begin (); i != placer.end (); ++i) {
+      transformations[i->second] = db::DCplxTrans (i->first.p1 () - org_boxes[i->second].p1 ());
+    }
+
+  }
+
+  {
+    view ()->cancel_edits ();
+    manager ()->transaction (tl::to_string (QObject::tr ("Distribution")));
+
+    //  do the distribution
+    for (std::vector<edt::Service *>::const_iterator es = edt_services.begin (); es != edt_services.end (); ++es) {
+
+      size_t ie = es - edt_services.begin ();
+
+      //  create a transformation vector that describes each shape's transformation
+      std::vector <db::DCplxTrans> tv (transformations.begin () + objects_for_service [ie].first, transformations.begin () + objects_for_service [ie].second);
+
+      //  use the "transform" method to transform the shapes and instances (with individual transformations)
+      (*es)->transform (db::DCplxTrans () /*dummy*/, &tv);
+
+    }
+
+    manager ()->commit ();
+
+  }
+}
+
+void
 MainService::cm_make_array ()
 {
   size_t n = 0;
@@ -1941,21 +2071,67 @@ MainService::cm_make_array ()
 void 
 MainService::cm_tap ()
 {
-  tl_assert (view ()->is_editable ());
-  check_no_guiding_shapes ();
+  if (! view ()->view_object_widget ()->mouse_in_window ()) {
+    return;
+  }
 
-  std::vector<edt::Service *> edt_services = view ()->get_plugins <edt::Service> ();
+  lay::ShapeFinder finder (true /*point mode*/, false /*all hierarchy levels*/, db::ShapeIterator::All, 0);
 
-  //  get (common) cellview index of the selected shapes
-  for (std::vector<edt::Service *>::const_iterator es = edt_services.begin (); es != edt_services.end (); ++es) {
-    for (edt::Service::obj_iterator s = (*es)->selection ().begin (); s != (*es)->selection ().end (); ++s) {
-      const lay::CellView &cv = view ()->cellview (s->cv_index ());
-      if (cv.is_valid () && ! s->is_cell_inst ()) {
-        view ()->set_current_layer (s->cv_index (), cv->layout ().get_properties (s->layer ()));
-        return;
-      }
+  //  capture all objects in point mode (default: capture one only)
+  finder.set_catch_all (true);
+
+  //  go through all visible layers of all cellviews
+  db::DPoint pt = view ()->view_object_widget ()->mouse_position_um ();
+  finder.find (view (), db::DBox (pt, pt));
+
+  std::set<std::pair<unsigned int, unsigned int> > layers_in_selection;
+
+  for (lay::ShapeFinder::iterator f = finder.begin (); f != finder.end (); ++f) {
+    //  ignore guiding shapes
+    if (f->layer () != view ()->cellview (f->cv_index ())->layout ().guiding_shape_layer ()) {
+      layers_in_selection.insert (std::make_pair (f->cv_index (), f->layer ()));
     }
   }
+
+  std::vector<lay::LayerPropertiesConstIterator> tapped_layers;
+  for (lay::LayerPropertiesConstIterator lp = view ()->begin_layers (view ()->current_layer_list ()); ! lp.at_end (); ++lp) {
+    const lay::LayerPropertiesNode *ln = lp.operator-> ();
+    if (layers_in_selection.find (std::make_pair ((unsigned int) ln->cellview_index (), (unsigned int) ln->layer_index ())) != layers_in_selection.end ()) {
+      tapped_layers.push_back (lp);
+    }
+  }
+
+  if (tapped_layers.empty ()) {
+    return;
+  }
+
+  //  List the layers under the cursor as pop up a menu
+
+  std::auto_ptr<QMenu> menu (new QMenu (view ()));
+  menu->show ();
+
+  int icon_size = menu->style ()->pixelMetric (QStyle::PM_ButtonIconSize);
+
+  QPoint mp = view ()->view_object_widget ()->mapToGlobal (view ()->view_object_widget ()->mouse_position ());
+
+  for (std::vector<lay::LayerPropertiesConstIterator>::const_iterator l = tapped_layers.begin (); l != tapped_layers.end (); ++l) {
+    QAction *a = menu->addAction (lay::LayerTreeModel::icon_for_layer (*l, view (), icon_size, icon_size, 0, true), tl::to_qstring ((*l)->source (true).to_string ()));
+    a->setData (int (l - tapped_layers.begin ()));
+  }
+
+  QAction *action = menu->exec (mp);
+  if (action) {
+
+    int index = action->data ().toInt ();
+    lay::LayerPropertiesConstIterator iter = tapped_layers [index];
+    view ()->set_current_layer (iter);
+
+    edt::Service *es = dynamic_cast<edt::Service *> (view ()->view_object_widget ()->active_service ());
+    if (es) {
+      es->tap (pt);
+    }
+
+  }
 }
 
 void 
@@ -1966,16 +2142,12 @@ MainService::cm_change_layer ()
 
   int cv_index = -1;
 
-  std::vector<edt::Service *> edt_services = view ()->get_plugins <edt::Service> ();
-
   //  get (common) cellview index of the selected shapes
-  for (std::vector<edt::Service *>::const_iterator es = edt_services.begin (); es != edt_services.end (); ++es) {
-    for (edt::Service::obj_iterator s = (*es)->selection ().begin (); s != (*es)->selection ().end (); ++s) {
-      if (cv_index >= 0 && cv_index != int (s->cv_index ())) {
-        throw tl::Exception (tl::to_string (QObject::tr ("Selections originate from different layouts - cannot switch layer in this case.")));
-      }
-      cv_index = int (s->cv_index ());
+  for (SelectionIterator s (view ()); ! s.at_end (); ++s) {
+    if (cv_index >= 0 && cv_index != int (s->cv_index ())) {
+      throw tl::Exception (tl::to_string (QObject::tr ("Selections originate from different layouts - cannot switch layer in this case.")));
     }
+    cv_index = int (s->cv_index ());
   }
 
   if (cv_index >= 0) {
@@ -2037,46 +2209,42 @@ MainService::cm_change_layer ()
 
     //  Insert and delete the shape. This exploits the fact, that a shape can be erased multiple times -
     //  this is important since the selection potentially contains the same shape multiple times.
-    for (std::vector<edt::Service *>::const_iterator es = edt_services.begin (); es != edt_services.end (); ++es) {
+    for (SelectionIterator s (view ()); ! s.at_end (); ++s) {
 
-      for (edt::Service::obj_iterator s = (*es)->selection ().begin (); s != (*es)->selection ().end (); ++s) {
+      if (!s->is_cell_inst () && int (s->layer ()) != layer) {
 
-        if (!s->is_cell_inst () && int (s->layer ()) != layer) {
+        db::Cell &cell = layout.cell (s->cell_index ());
+        if (cell.shapes (s->layer ()).is_valid (s->shape ())) {
+          cell.shapes (layer).insert (s->shape ());
+          cell.shapes (s->layer ()).erase_shape (s->shape ());
+        }
 
-          db::Cell &cell = layout.cell (s->cell_index ());
-          if (cell.shapes (s->layer ()).is_valid (s->shape ())) {
-            cell.shapes (layer).insert (s->shape ());
-            cell.shapes (s->layer ()).erase_shape (s->shape ());
-          }
+      } else if (s->is_cell_inst ()) {
 
-        } else if (s->is_cell_inst ()) {
+        //  If the selected object is a PCell instance, and there is exactly one visible, writable layer type parameter, change this one
 
-          //  If the selected object is a PCell instance, and there is exactly one visible, writable layer type parameter, change this one
+        db::Instance inst = s->back ().inst_ptr;
+        db::Cell &cell = layout.cell (s->cell_index ());
 
-          db::Instance inst = s->back ().inst_ptr;
-          db::Cell &cell = layout.cell (s->cell_index ());
+        if (cell.is_valid (inst)) {
 
-          if (cell.is_valid (inst)) {
+          const db::PCellDeclaration *pcell_decl = layout.pcell_declaration_for_pcell_variant (inst.cell_index ());
+          if (pcell_decl) {
 
-            const db::PCellDeclaration *pcell_decl = layout.pcell_declaration_for_pcell_variant (inst.cell_index ());
-            if (pcell_decl) {
-
-              size_t layer_par_index = 0;
-              int n_layer_par = 0;
-              for (std::vector<db::PCellParameterDeclaration>::const_iterator d = pcell_decl->parameter_declarations ().begin (); d != pcell_decl->parameter_declarations ().end () && n_layer_par < 2; ++d) {
-                if (d->get_type () == db::PCellParameterDeclaration::t_layer && !d->is_hidden () && !d->is_readonly ()) {
-                  ++n_layer_par;
-                  layer_par_index = size_t (d - pcell_decl->parameter_declarations ().begin ());
-                }
-              }
-
-              if (n_layer_par == 1) {
-                std::vector<tl::Variant> parameters = cell.get_pcell_parameters (inst);
-                tl_assert (layer_par_index < parameters.size ());
-                parameters [layer_par_index] = layout.get_properties (layer);
-                cell.change_pcell_parameters (inst, parameters);
+            size_t layer_par_index = 0;
+            int n_layer_par = 0;
+            for (std::vector<db::PCellParameterDeclaration>::const_iterator d = pcell_decl->parameter_declarations ().begin (); d != pcell_decl->parameter_declarations ().end () && n_layer_par < 2; ++d) {
+              if (d->get_type () == db::PCellParameterDeclaration::t_layer && !d->is_hidden () && !d->is_readonly ()) {
+                ++n_layer_par;
+                layer_par_index = size_t (d - pcell_decl->parameter_declarations ().begin ());
               }
+            }
 
+            if (n_layer_par == 1) {
+              std::vector<tl::Variant> parameters = cell.get_pcell_parameters (inst);
+              tl_assert (layer_par_index < parameters.size ());
+              parameters [layer_par_index] = layout.get_properties (layer);
+              cell.change_pcell_parameters (inst, parameters);
             }
 
           }
@@ -2101,12 +2269,6 @@ MainService::cm_change_layer ()
 
 }
 
-void  
-MainService::cm_edit_options ()
-{
-  show_editor_options_dialog ();
-}
-
 void
 MainService::check_no_guiding_shapes ()
 {
diff --git a/src/edt/edt/edtMainService.h b/src/edt/edt/edtMainService.h
index 743d8a9f4..c2f5c97ec 100644
--- a/src/edt/edt/edtMainService.h
+++ b/src/edt/edt/edtMainService.h
@@ -51,6 +51,7 @@ class RoundCornerOptionsDialog;
 class MakeCellOptionsDialog;
 class MakeArrayOptionsDialog;
 class AlignOptionsDialog;
+class DistributeOptionsDialog;
 
 // -------------------------------------------------------------
 
@@ -93,11 +94,6 @@ public:
    */
   void cm_ascend ();
 
-  /**
-   *  @brief Edit object options
-   */
-  void cm_edit_options ();
-
   /**
    *  @brief Change the layer of the shapes in the selection
    */
@@ -153,6 +149,11 @@ public:
    */
   void cm_align ();
 
+  /**
+   *  @brief Distribute the selected shapes and instances
+   */
+  void cm_distribute ();
+
   /**
    *  @brief Flatten instances
    */
@@ -205,6 +206,13 @@ private:
   int m_align_hmode;
   int m_align_vmode;
   bool m_align_visible_layers;
+  bool m_hdistribute;
+  int m_distribute_hmode;
+  double m_distribute_hpitch, m_distribute_hspace;
+  bool m_vdistribute;
+  int m_distribute_vmode;
+  double m_distribute_vpitch, m_distribute_vspace;
+  bool m_distribute_visible_layers;
   std::string m_make_cell_name;
   int m_origin_mode_x, m_origin_mode_y;
   bool m_origin_visible_layers_for_bbox;
@@ -215,6 +223,7 @@ private:
   bool m_undo_before_apply;
   edt::RoundCornerOptionsDialog *mp_round_corners_dialog;
   edt::AlignOptionsDialog *mp_align_options_dialog;
+  edt::DistributeOptionsDialog *mp_distribute_options_dialog;
   lay::FlattenInstOptionsDialog *mp_flatten_inst_options_dialog;
   edt::MakeCellOptionsDialog *mp_make_cell_options_dialog;
   edt::MakeArrayOptionsDialog *mp_make_array_options_dialog;
@@ -223,6 +232,7 @@ private:
   void check_no_guiding_shapes ();
   edt::RoundCornerOptionsDialog *round_corners_dialog ();
   edt::AlignOptionsDialog *align_options_dialog ();
+  edt::DistributeOptionsDialog *distribute_options_dialog ();
   lay::FlattenInstOptionsDialog *flatten_inst_options_dialog ();
   edt::MakeCellOptionsDialog *make_cell_options_dialog ();
   edt::MakeArrayOptionsDialog *make_array_options_dialog ();
diff --git a/src/edt/edt/edtPCellParametersDialog.cc b/src/edt/edt/edtPCellParametersDialog.cc
deleted file mode 100644
index bdb33b47f..000000000
--- a/src/edt/edt/edtPCellParametersDialog.cc
+++ /dev/null
@@ -1,65 +0,0 @@
-
-/*
-
-  KLayout Layout Viewer
-  Copyright (C) 2006-2020 Matthias Koefferlein
-
-  This program is free software; you can redistribute it and/or modify
-  it under the terms of the GNU General Public License as published by
-  the Free Software Foundation; either version 2 of the License, or
-  (at your option) any later version.
-
-  This program is distributed in the hope that it will be useful,
-  but WITHOUT ANY WARRANTY; without even the implied warranty of
-  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
-  GNU General Public License for more details.
-
-  You should have received a copy of the GNU General Public License
-  along with this program; if not, write to the Free Software
-  Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
-
-*/
-
-
-#include "edtPCellParametersDialog.h"
-
-#include <QPushButton>
-
-namespace edt
-{
-
-PCellParametersDialog::PCellParametersDialog (QWidget *parent)
-  : QDialog (parent)
-{
-  setupUi (this);
-
-  connect (buttons->button (QDialogButtonBox::Apply), SIGNAL (clicked ()), this, SLOT (apply_pressed ()));
-}
-
-void
-PCellParametersDialog::apply_pressed ()
-{
-  emit parameters_changed ();
-  parameters_changed_event ();
-}
-
-std::vector<tl::Variant> 
-PCellParametersDialog::get_parameters () 
-{
-  return parameters->get_parameters ();
-}
-
-void 
-PCellParametersDialog::set_parameters (const std::vector<tl::Variant> &p)
-{
-  parameters->set_parameters (p);
-}
-
-int
-PCellParametersDialog::exec (const db::Layout *layout, lay::LayoutView *view, int cv_index, const db::PCellDeclaration *pcell_decl, const db::pcell_parameters_type &p)
-{
-  parameters->setup (layout, view, cv_index, pcell_decl, p);
-  return QDialog::exec ();
-}
-
-}
diff --git a/src/edt/edt/edtPCellParametersDialog.h b/src/edt/edt/edtPCellParametersDialog.h
deleted file mode 100644
index 2a977a4cd..000000000
--- a/src/edt/edt/edtPCellParametersDialog.h
+++ /dev/null
@@ -1,86 +0,0 @@
-
-/*
-
-  KLayout Layout Viewer
-  Copyright (C) 2006-2020 Matthias Koefferlein
-
-  This program is free software; you can redistribute it and/or modify
-  it under the terms of the GNU General Public License as published by
-  the Free Software Foundation; either version 2 of the License, or
-  (at your option) any later version.
-
-  This program is distributed in the hope that it will be useful,
-  but WITHOUT ANY WARRANTY; without even the implied warranty of
-  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
-  GNU General Public License for more details.
-
-  You should have received a copy of the GNU General Public License
-  along with this program; if not, write to the Free Software
-  Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
-
-*/
-
-
-#ifndef HDR_edtPCellParametersDialog
-#define HDR_edtPCellParametersDialog
-
-#include "dbPCellDeclaration.h"
-#include "ui_PCellParametersDialog.h"
-
-#include <QDialog>
-
-namespace lay
-{
-  class LayoutView;
-}
-
-namespace edt
-{
-
-/**
- *  @brief A QScrollArea that displays and allows editing PCell parameters
- */
-class PCellParametersDialog
-  : public QDialog, private Ui::PCellParametersDialog
-{
-Q_OBJECT
-
-public:
-  /**
-   *  @brief Constructor: create a dialog showing the given parameters
-   *  @param parent The parent widget
-   */
-  PCellParametersDialog (QWidget *parent);
-
-  /**
-   *  @brief Executes the parameter dialog
-   *  @param layout The layout in which the PCell instance resides
-   *  @param view The layout view from which to take layers for example
-   *  @param cv_index The index of the cellview in "view"
-   *  @param pcell_decl The PCell declaration
-   *  @param parameters The parameter values to show (if empty, the default values are used)
-   */
-  int exec (const db::Layout *layout, lay::LayoutView *view, int cv_index, const db::PCellDeclaration *pcell_decl, const db::pcell_parameters_type &p);
-
-  /**
-   *  @brief Get the current parameters
-   */
-  std::vector<tl::Variant> get_parameters ();
-
-  /**
-   *  @brief Sets the given parameters as values
-   */
-  void set_parameters (const  std::vector<tl::Variant> &values);
-
-  tl::Event parameters_changed_event;
-
-signals:
-  void parameters_changed ();
-
-private slots:
-  void apply_pressed ();
-};
-
-}
-
-#endif
diff --git a/src/edt/edt/edtPCellParametersPage.cc b/src/edt/edt/edtPCellParametersPage.cc
index 87ab6d3e4..01b667002 100644
--- a/src/edt/edt/edtPCellParametersPage.cc
+++ b/src/edt/edt/edtPCellParametersPage.cc
@@ -22,7 +22,9 @@
 
 
 #include "edtPCellParametersPage.h"
+#include "edtPropertiesPageUtils.h"
 #include "layWidgets.h"
+#include "layQtTools.h"
 #include "tlScriptError.h"
 
 #include <QFrame>
@@ -142,15 +144,8 @@ static void set_value (const db::PCellParameterDeclaration &p, const db::Layout
   }
 }
 
-PCellParametersPage::PCellParametersPage (QWidget *parent, const db::Layout *layout, lay::LayoutView *view, int cv_index, const db::PCellDeclaration *pcell_decl, const db::pcell_parameters_type &parameters)
-  : QFrame (parent)
-{
-  init ();
-  setup (layout, view, cv_index, pcell_decl, parameters);
-}
-
-PCellParametersPage::PCellParametersPage (QWidget *parent)
-  : QFrame (parent)
+PCellParametersPage::PCellParametersPage (QWidget *parent, bool dense)
+  : QFrame (parent), m_dense (dense), dm_parameter_changed (this, &PCellParametersPage::do_parameter_changed)
 {
   init ();
 }
@@ -165,6 +160,8 @@ PCellParametersPage::init ()
   mp_parameters_area = 0;
 
   QGridLayout *frame_layout = new QGridLayout (this);
+  //  spacing and margin for tool windows
+  frame_layout->setMargin (0);
   setLayout (frame_layout);
 
   mp_error_icon = new QLabel (this);
@@ -173,6 +170,7 @@ PCellParametersPage::init ()
   frame_layout->addWidget (mp_error_icon, 1, 0, 1, 1);
 
   mp_error_label = new QLabel (this);
+  mp_error_label->setWordWrap (true);
   QPalette palette = mp_error_label->palette ();
   palette.setColor (QPalette::Foreground, Qt::red);
   mp_error_label->setPalette (palette);
@@ -200,6 +198,7 @@ PCellParametersPage::setup (const db::Layout *layout, lay::LayoutView *view, int
   m_widgets.clear ();
 
   mp_parameters_area = new QScrollArea (this);
+  mp_parameters_area->setFrameShape (QFrame::NoFrame);
   QGridLayout *frame_layout = dynamic_cast<QGridLayout *> (QFrame::layout ());
   frame_layout->addWidget (mp_parameters_area, 0, 0, 1, 2);
   frame_layout->setRowStretch (0, 1);
@@ -211,6 +210,11 @@ PCellParametersPage::setup (const db::Layout *layout, lay::LayoutView *view, int
 
   QGridLayout *inner_grid = new QGridLayout (inner_frame);
   inner_frame->setLayout (inner_grid);
+  if (m_dense) {
+    inner_grid->setMargin (4);
+    inner_grid->setHorizontalSpacing (6);
+    inner_grid->setVerticalSpacing (2);
+  }
 
   QWidget *main_frame = inner_frame;
   QGridLayout *main_grid = inner_grid;
@@ -247,6 +251,11 @@ PCellParametersPage::setup (const db::Layout *layout, lay::LayoutView *view, int
         main_grid->addWidget (gb, main_row, 0, 1, 2);
         
         inner_grid = new QGridLayout (gb);
+        if (m_dense) {
+          inner_grid->setMargin (4);
+          inner_grid->setHorizontalSpacing (6);
+          inner_grid->setVerticalSpacing (2);
+        }
         gb->setLayout (inner_grid);
         inner_frame = gb;
 
@@ -286,11 +295,13 @@ PCellParametersPage::setup (const db::Layout *layout, lay::LayoutView *view, int
           QHBoxLayout *hb = new QHBoxLayout (f);
           hb->setMargin (0);
           f->setLayout (hb);
+          f->setFrameShape (QFrame::NoFrame);
 
           QLineEdit *le = new QLineEdit (f);
           le->setEnabled (! p->is_readonly ());
           hb->addWidget (le);
           le->setMaximumWidth (150);
+          le->setObjectName (tl::to_qstring (p->get_name ()));
           m_widgets.push_back (le);
 
           QLabel *ul = new QLabel (f);
@@ -299,7 +310,7 @@ PCellParametersPage::setup (const db::Layout *layout, lay::LayoutView *view, int
 
           inner_grid->addWidget (f, row, 1);
 
-          connect (le, SIGNAL (editingFinished ()), this, SLOT (activated ()));
+          connect (le, SIGNAL (editingFinished ()), this, SLOT (parameter_changed ()));
         }
         break;
 
@@ -309,10 +320,11 @@ PCellParametersPage::setup (const db::Layout *layout, lay::LayoutView *view, int
         {
           QLineEdit *le = new QLineEdit (inner_frame);
           le->setEnabled (! p->is_readonly ());
+          le->setObjectName (tl::to_qstring (p->get_name ()));
           m_widgets.push_back (le);
           inner_grid->addWidget (le, row, 1);
 
-          connect (le, SIGNAL (editingFinished ()), this, SLOT (activated ()));
+          connect (le, SIGNAL (editingFinished ()), this, SLOT (parameter_changed ()));
         }
         break;
 
@@ -322,19 +334,25 @@ PCellParametersPage::setup (const db::Layout *layout, lay::LayoutView *view, int
           ly->setEnabled (! p->is_readonly ());
           ly->set_no_layer_available (true);
           ly->set_view (mp_view, m_cv_index, true /*all layers*/);
+          ly->setObjectName (tl::to_qstring (p->get_name ()));
           m_widgets.push_back (ly);
           inner_grid->addWidget (ly, row, 1);
+
+          connect (ly, SIGNAL (activated (int)), this, SLOT (parameter_changed ()));
         }
         break;
 
       case db::PCellParameterDeclaration::t_boolean:
         {
           QCheckBox *cbx = new QCheckBox (inner_frame);
+          //  this makes the checkbox not stretch over the full width - better when navigating with tab
+          cbx->setSizePolicy (QSizePolicy (QSizePolicy::Fixed, QSizePolicy::Preferred));
           cbx->setEnabled (! p->is_readonly ());
+          cbx->setObjectName (tl::to_qstring (p->get_name ()));
           m_widgets.push_back (cbx);
           inner_grid->addWidget (cbx, row, 1);
 
-          connect (cbx, SIGNAL (stateChanged (int)), this, SLOT (activated ()));
+          connect (cbx, SIGNAL (stateChanged (int)), this, SLOT (parameter_changed ()));
         }
         break;
 
@@ -346,6 +364,7 @@ PCellParametersPage::setup (const db::Layout *layout, lay::LayoutView *view, int
     } else {
 
       QComboBox *cb = new QComboBox (inner_frame);
+      cb->setObjectName (tl::to_qstring (p->get_name ()));
 
       int i = 0;
       for (std::vector<tl::Variant>::const_iterator c = p->get_choices ().begin (); c != p->get_choices ().end (); ++c, ++i) {
@@ -356,7 +375,8 @@ PCellParametersPage::setup (const db::Layout *layout, lay::LayoutView *view, int
         }
       }
 
-      connect (cb, SIGNAL (activated (int)), this, SLOT (activated ()));
+      connect (cb, SIGNAL (activated (int)), this, SLOT (parameter_changed ()));
+
       cb->setEnabled (! p->is_readonly ());
       cb->setMinimumContentsLength (30);
       cb->setSizeAdjustPolicy (QComboBox::AdjustToMinimumContentsLengthWithIcon);
@@ -377,17 +397,24 @@ PCellParametersPage::setup (const db::Layout *layout, lay::LayoutView *view, int
   mp_parameters_area->setWidget (main_frame);
   main_frame->show ();
 
-  //  does a first coerce and update
-  get_parameters ();
+  //  does a first coerce and update. Ignore errors for now.
+  bool ok = false;
+  get_parameters (&ok);
 }
 
 PCellParametersPage::State
 PCellParametersPage::get_state ()
 {
   State s;
+
   s.valid = true;
   s.vScrollPosition = mp_parameters_area->verticalScrollBar ()->value ();
   s.hScrollPosition = mp_parameters_area->horizontalScrollBar ()->value ();
+
+  if (focusWidget ()) {
+    s.focusWidget = focusWidget ()->objectName ();
+  }
+
   return s;
 }
 
@@ -395,29 +422,42 @@ void
 PCellParametersPage::set_state (const State &s)
 {
   if (s.valid) {
+
     mp_parameters_area->verticalScrollBar ()->setValue (s.vScrollPosition);
     mp_parameters_area->horizontalScrollBar ()->setValue (s.hScrollPosition);
+
+    if (! s.focusWidget.isEmpty ()) {
+      QWidget *c = findChild<QWidget *> (s.focusWidget);
+      if (c) {
+        c->setFocus ();
+      }
+    }
+
   }
 }
 
 void  
-PCellParametersPage::activated ()
+PCellParametersPage::parameter_changed ()
 {
-  //  does a coerce and update
-  get_parameters ();
+  dm_parameter_changed ();
 }
 
-void  
-PCellParametersPage::clicked ()
+void
+PCellParametersPage::do_parameter_changed ()
 {
   //  does a coerce and update
-  get_parameters ();
+  bool ok = false;
+  get_parameters (&ok);
+  if (ok) {
+    emit edited ();
+  }
 }
 
 std::vector<tl::Variant> 
-PCellParametersPage::get_parameters () 
+PCellParametersPage::get_parameters (bool *ok)
 {
   std::vector<tl::Variant> parameters;
+  bool edit_error = true;
 
   int r = 0;
   const std::vector<db::PCellParameterDeclaration> &pcp = mp_pcell_decl->parameter_declarations ();
@@ -443,9 +483,22 @@ PCellParametersPage::get_parameters ()
           {
             QLineEdit *le = dynamic_cast<QLineEdit *> (m_widgets [r]);
             if (le) {
-              int v = 0;
-              tl::from_string (tl::to_string (le->text ()), v);
-              parameters.back () = tl::Variant (v);
+
+              try {
+
+                int v = 0;
+                tl::from_string (tl::to_string (le->text ()), v);
+
+                parameters.back () = tl::Variant (v);
+                lay::indicate_error (le, 0);
+
+              } catch (tl::Exception &ex) {
+
+                lay::indicate_error (le, &ex);
+                edit_error = false;
+
+              }
+
             }
           }
           break;
@@ -454,9 +507,22 @@ PCellParametersPage::get_parameters ()
           {
             QLineEdit *le = dynamic_cast<QLineEdit *> (m_widgets [r]);
             if (le) {
-              double v = 0;
-              tl::from_string (tl::to_string (le->text ()), v);
-              parameters.back () = tl::Variant (v);
+
+              try {
+
+                double v = 0;
+                tl::from_string (tl::to_string (le->text ()), v);
+
+                parameters.back () = tl::Variant (v);
+                lay::indicate_error (le, 0);
+
+              } catch (tl::Exception &ex) {
+
+                lay::indicate_error (le, &ex);
+                edit_error = false;
+
+              }
+
             }
           }
           break;
@@ -516,22 +582,43 @@ PCellParametersPage::get_parameters ()
 
   try {
 
+    if (! edit_error) {
+      throw tl::Exception (tl::to_string (tr ("There are errors. See the highlighted edit fields for details.")));
+    }
+
     //  coerce the parameters
     mp_pcell_decl->coerce_parameters (*mp_layout, parameters);
     set_parameters (parameters);
 
+    mp_error_label->hide ();
+    mp_error_icon->hide ();
+
+    if (ok) {
+      *ok = true;
+    }
+
   } catch (tl::ScriptError &ex) {
 
-    mp_error_label->setText (tl::to_qstring (ex.basic_msg ()));
-    mp_error_label->setToolTip (tl::to_qstring (ex.msg ()));
-    mp_error_icon->show ();
-    mp_error_label->show ();
+    if (ok) {
+      mp_error_label->setText (tl::to_qstring (ex.basic_msg ()));
+      mp_error_label->setToolTip (tl::to_qstring (ex.msg ()));
+      mp_error_icon->show ();
+      mp_error_label->show ();
+      *ok = false;
+    } else {
+      throw;
+    }
 
   } catch (tl::Exception &ex) {
 
-    mp_error_label->setText (tl::to_qstring (ex.msg ()));
-    mp_error_icon->show ();
-    mp_error_label->show ();
+    if (ok) {
+      mp_error_label->setText (tl::to_qstring (ex.msg ()));
+      mp_error_icon->show ();
+      mp_error_label->show ();
+      *ok = false;
+    } else {
+      throw;
+    }
 
   }
 
@@ -539,7 +626,7 @@ PCellParametersPage::get_parameters ()
 }
 
 void 
-PCellParametersPage::set_parameters (const  std::vector<tl::Variant> &parameters) 
+PCellParametersPage::set_parameters (const std::vector<tl::Variant> &parameters)
 {
   //  write the changed value back
   size_t r = 0;
diff --git a/src/edt/edt/edtPCellParametersPage.h b/src/edt/edt/edtPCellParametersPage.h
index a41a7c233..9786a2c8b 100644
--- a/src/edt/edt/edtPCellParametersPage.h
+++ b/src/edt/edt/edtPCellParametersPage.h
@@ -25,6 +25,7 @@
 #define HDR_edtPCellParametersPage
 
 #include "dbPCellDeclaration.h"
+#include "tlDeferredExecution.h"
 
 #include <QFrame>
 #include <QScrollArea>
@@ -42,7 +43,7 @@ namespace edt
  *  @brief A QScrollArea that displays and allows editing PCell parameters
  */
 class PCellParametersPage
-  : public QFrame
+  : public QFrame, public tl::Object
 {
 Q_OBJECT
 
@@ -54,31 +55,28 @@ public:
     bool valid;
     int hScrollPosition;
     int vScrollPosition;
+    QString focusWidget;
   };
 
-  /**
-   *  @brief Constructor: creates a page showing the given parameters
-   *
-   *  @param parent The parent widget
-   *  @param layout The layout in which the PCell instance resides
-   *  @param view The layout view from which to take layers for example
-   *  @param cv_index The index of the cellview in "view"
-   *  @param pcell_decl The PCell declaration
-   *  @param parameters The parameter values to show (if empty, the default values are used)
-   */
-  PCellParametersPage (QWidget *parent, const db::Layout *layout, lay::LayoutView *view, int cv_index, const db::PCellDeclaration *pcell_decl, const db::pcell_parameters_type &parameters);
-
   /**
    *  @brief Default constructor
    *
    *  Use "setup" to configure the page.
+   *
+   *  @param dense Use a dense layout if true
    */
-  PCellParametersPage (QWidget *parent);
+  PCellParametersPage (QWidget *parent, bool dense = false);
 
   /**
-   *  @brief Delayed initialization
+   *  @brief initialization
    *
    *  Use this method to setup when the arguments are not available in the constructor
+   *
+   *  @param layout The layout in which the PCell instance resides
+   *  @param view The layout view from which to take layers for example
+   *  @param cv_index The index of the cellview in "view"
+   *  @param pcell_decl The PCell declaration
+   *  @param parameters The parameter values to show (if empty, the default values are used)
    */
   void setup (const db::Layout *layout, lay::LayoutView *view, int cv_index, const db::PCellDeclaration *pcell_decl, const db::pcell_parameters_type &parameters);
 
@@ -94,8 +92,12 @@ public:
 
   /**
    *  @brief Get the current parameters
+   *
+   *  *ok is set to true, if there is no error. In case of an error it's set to false.
+   *  The error is indicated in the error label in the editor page.
+   *  If ok is null, an exception is thrown.
    */
-  std::vector<tl::Variant> get_parameters ();
+  std::vector<tl::Variant> get_parameters (bool *ok = 0);
 
   /**
    *  @brief Get the PCell declaration pointer
@@ -110,10 +112,12 @@ public:
    */
   void set_parameters (const  std::vector<tl::Variant> &values);
 
-public slots:
-  void activated ();
-  void clicked ();
-  
+signals:
+  void edited ();
+
+private slots:
+  void parameter_changed ();
+
 private:
   QScrollArea *mp_parameters_area;
   QLabel *mp_error_label;
@@ -124,8 +128,11 @@ private:
   lay::LayoutView *mp_view;
   int m_cv_index;
   db::pcell_parameters_type m_parameters;
+  bool m_dense;
+  tl::DeferredMethod<PCellParametersPage> dm_parameter_changed;
 
   void init ();
+  void do_parameter_changed ();
 };
 
 }
diff --git a/src/edt/edt/edtPartialService.cc b/src/edt/edt/edtPartialService.cc
index 63952ed28..dac20b299 100644
--- a/src/edt/edt/edtPartialService.cc
+++ b/src/edt/edt/edtPartialService.cc
@@ -32,6 +32,7 @@
 #include "edtService.h"
 #include "edtConfig.h"
 #include "edtDialogs.h"
+#include "edtPlugin.h"
 #include "edtEditorOptionsPages.h"
 
 #include <cmath>
@@ -1009,9 +1010,7 @@ PartialShapeFinder::visit_cell (const db::Cell &cell, const db::Box &search_box,
 
 PartialService::PartialService (db::Manager *manager, lay::LayoutView *view, lay::Dispatcher *root)
   : QObject (),
-    lay::ViewService (view->view_object_widget ()), 
-    lay::Editable (view),
-    lay::Plugin (view),
+    lay::EditorServiceBase (view),
     db::Object (manager),
     mp_view (view),
     mp_root (root),
@@ -1069,7 +1068,7 @@ PartialService::deactivated ()
 void  
 PartialService::activated ()
 {
-  // ... 
+  //  .. nothing yet ..
 }
 
 void 
@@ -1294,11 +1293,11 @@ PartialService::snap (const db::DVector &v) const
 
 const int sr_pixels = 8; //  TODO: make variable
 
-db::DPoint 
+lay::PointSnapToObjectResult
 PartialService::snap2 (const db::DPoint &p) const
 {
   double snap_range = widget ()->mouse_event_trans ().inverted ().ctrans (sr_pixels);
-  return lay::obj_snap (m_snap_to_objects ? view () : 0, p, m_edit_grid == db::DVector () ? m_global_grid : m_edit_grid, snap_range).second;
+  return lay::obj_snap (m_snap_to_objects ? view () : 0, p, m_edit_grid == db::DVector () ? m_global_grid : m_edit_grid, snap_range);
 }
 
 void
@@ -1530,20 +1529,27 @@ PartialService::wheel_event (int /*delta*/, bool /*horizonal*/, const db::DPoint
 bool  
 PartialService::mouse_move_event (const db::DPoint &p, unsigned int buttons, bool prio)
 {
+  clear_mouse_cursors ();
+
   if (m_dragging) {
 
     set_cursor (lay::Cursor::size_all);
 
     m_alt_ac = ac_from_buttons (buttons);
 
-    // drag the vertex or edge/segment
+    lay::PointSnapToObjectResult snap_details;
+
+    //  drag the vertex or edge/segment
     if (is_single_point_selection ()) {
-      //  for a single selected point, m_start is the original position and we snap the target - 
-      //  thus, we can bring the point on grid or to an object's edge or vertex 
-      m_current = snap2 (p);
+      //  for a single selected point, m_start is the original position and we snap the target -
+      //  thus, we can bring the point on grid or to an object's edge or vertex
+      snap_details = snap2 (p);
+      m_current = snap_details.snapped_point;
     } else {
       m_current = m_start + snap (p - m_start);
     }
+
+    mouse_cursor_from_snap_details (snap_details);
     selection_to_view ();
 
     m_alt_ac = lay::AC_Global;
diff --git a/src/edt/edt/edtPartialService.h b/src/edt/edt/edtPartialService.h
index 2c22ac21c..f38b994a0 100644
--- a/src/edt/edt/edtPartialService.h
+++ b/src/edt/edt/edtPartialService.h
@@ -25,10 +25,8 @@
 #ifndef HDR_edtPartialService
 #define HDR_edtPartialService
 
-#include "layEditable.h"
+#include "layEditorServiceBase.h"
 #include "layObjectInstPath.h"
-#include "layLayoutView.h"
-#include "layPlugin.h"
 #include "layViewObject.h"
 #include "layRubberBox.h"
 #include "laySnap.h"
@@ -140,9 +138,7 @@ struct EdgeWithIndex
  */
 class PartialService
   : public QObject,
-    public lay::ViewService,
-    public lay::Editable,
-    public lay::Plugin,
+    public lay::EditorServiceBase,
     public db::Object
 {
 Q_OBJECT
@@ -326,7 +322,7 @@ private:
 
   db::DPoint snap (const db::DPoint &p) const;
   db::DVector snap (const db::DVector &p) const;
-  db::DPoint snap2 (const db::DPoint &p) const;
+  lay::PointSnapToObjectResult snap2 (const db::DPoint &p) const;
 
   void enter_edge (const EdgeWithIndex &e, size_t &nmarker, partial_objects::const_iterator sel, const std::map <PointWithIndex, db::Point> &new_points, const std::map <EdgeWithIndex, db::Edge> &new_edges, const db::ICplxTrans &gt, const std::vector<db::DCplxTrans> &tv, bool transient);
   void enter_vertices (size_t &nmarker, partial_objects::const_iterator sel, const std::map <PointWithIndex, db::Point> &new_points, const std::map <EdgeWithIndex, db::Edge> &new_edges, const db::ICplxTrans &gt, const std::vector<db::DCplxTrans> &tv, bool transient);
diff --git a/src/edt/edt/edtPlugin.cc b/src/edt/edt/edtPlugin.cc
index 53e7f2753..7caa8288b 100644
--- a/src/edt/edt/edtPlugin.cc
+++ b/src/edt/edt/edtPlugin.cc
@@ -22,6 +22,9 @@
 
 
 #include "layTipDialog.h"
+#include "layEditorOptionsPages.h"
+#include "layDispatcher.h"
+#include "layLayoutView.h"
 #include "edtPlugin.h"
 #include "edtConfig.h"
 #include "edtService.h"
@@ -29,13 +32,27 @@
 #include "edtMainService.h"
 #include "edtPartialService.h"
 #include "edtEditorOptionsPages.h"
+#include "edtRecentConfigurationPage.h"
 
 #include <QApplication>
+#include <QLayout>
 
 namespace edt
 {
 
-static 
+edt::RecentConfigurationPage::ConfigurationDescriptor shape_cfg_descriptors[] =
+{
+  edt::RecentConfigurationPage::ConfigurationDescriptor ("", tl::to_string (tr ("Layer")), edt::RecentConfigurationPage::Layer),
+};
+
+static
+void get_shape_editor_options_pages (std::vector<lay::EditorOptionsPage *> &ret, lay::LayoutView *view, lay::Dispatcher *dispatcher)
+{
+  ret.push_back (new RecentConfigurationPage (view, dispatcher, "edit-recent-shape-param",
+                        &shape_cfg_descriptors[0], &shape_cfg_descriptors[sizeof (shape_cfg_descriptors) / sizeof (shape_cfg_descriptors[0])]));
+}
+
+static
 void get_text_options (std::vector < std::pair<std::string, std::string> > &options)
 {
   options.push_back (std::pair<std::string, std::string> (cfg_edit_text_string, "ABC"));
@@ -44,10 +61,21 @@ void get_text_options (std::vector < std::pair<std::string, std::string> > &opti
   options.push_back (std::pair<std::string, std::string> (cfg_edit_text_valign, "bottom"));
 }
 
-static 
-void get_text_editor_options_pages (std::vector<edt::EditorOptionsPage *> &ret, lay::Dispatcher *)
+edt::RecentConfigurationPage::ConfigurationDescriptor text_cfg_descriptors[] =
 {
-  ret.push_back (new edt::EditorOptionsText ());
+  edt::RecentConfigurationPage::ConfigurationDescriptor ("", tl::to_string (tr ("Layer")), edt::RecentConfigurationPage::Layer),
+  edt::RecentConfigurationPage::ConfigurationDescriptor (cfg_edit_text_string, tl::to_string (tr ("Text")), edt::RecentConfigurationPage::Text),
+  edt::RecentConfigurationPage::ConfigurationDescriptor (cfg_edit_text_size, tl::to_string (tr ("Size")), edt::RecentConfigurationPage::Double),
+  edt::RecentConfigurationPage::ConfigurationDescriptor (cfg_edit_text_halign, tl::to_string (tr ("Hor. align")), edt::RecentConfigurationPage::Text),
+  edt::RecentConfigurationPage::ConfigurationDescriptor (cfg_edit_text_valign, tl::to_string (tr ("Vert. align")), edt::RecentConfigurationPage::Text)
+};
+
+static
+void get_text_editor_options_pages (std::vector<lay::EditorOptionsPage *> &ret, lay::LayoutView *view, lay::Dispatcher *dispatcher)
+{
+  ret.push_back (new RecentConfigurationPage (view, dispatcher, "edit-recent-text-param",
+                        &text_cfg_descriptors[0], &text_cfg_descriptors[sizeof (text_cfg_descriptors) / sizeof (text_cfg_descriptors[0])]));
+  ret.push_back (new edt::EditorOptionsText (dispatcher));
 }
 
 static 
@@ -59,10 +87,21 @@ void get_path_options (std::vector < std::pair<std::string, std::string> > &opti
   options.push_back (std::pair<std::string, std::string> (cfg_edit_path_ext_var_end, "0.0"));
 }
 
-static 
-void get_path_editor_options_pages (std::vector<edt::EditorOptionsPage *> &ret, lay::Dispatcher *)
+edt::RecentConfigurationPage::ConfigurationDescriptor path_cfg_descriptors[] =
 {
-  ret.push_back (new EditorOptionsPath ());
+  edt::RecentConfigurationPage::ConfigurationDescriptor ("", tl::to_string (tr ("Layer")), edt::RecentConfigurationPage::Layer),
+  edt::RecentConfigurationPage::ConfigurationDescriptor (cfg_edit_path_width, tl::to_string (tr ("Width")), edt::RecentConfigurationPage::Double),
+  edt::RecentConfigurationPage::ConfigurationDescriptor (cfg_edit_path_ext_type, tl::to_string (tr ("Ends")), edt::RecentConfigurationPage::Int),
+  edt::RecentConfigurationPage::ConfigurationDescriptor (cfg_edit_path_ext_var_begin, tl::to_string (tr ("Begin ext.")), edt::RecentConfigurationPage::Double),
+  edt::RecentConfigurationPage::ConfigurationDescriptor (cfg_edit_path_ext_var_end, tl::to_string (tr ("End ext.")), edt::RecentConfigurationPage::Double)
+};
+
+static
+void get_path_editor_options_pages (std::vector<lay::EditorOptionsPage *> &ret, lay::LayoutView *view, lay::Dispatcher *dispatcher)
+{
+  ret.push_back (new RecentConfigurationPage (view, dispatcher, "edit-recent-path-param",
+                        &path_cfg_descriptors[0], &path_cfg_descriptors[sizeof (path_cfg_descriptors) / sizeof (path_cfg_descriptors[0])]));
+  ret.push_back (new EditorOptionsPath (dispatcher));
 }
 
 static 
@@ -84,10 +123,30 @@ void get_inst_options (std::vector < std::pair<std::string, std::string> > &opti
   options.push_back (std::pair<std::string, std::string> (cfg_edit_show_shapes_of_instances, "true"));
 }
 
-static 
-void get_inst_editor_options_pages (std::vector<edt::EditorOptionsPage *> &ret, lay::Dispatcher *root)
+edt::RecentConfigurationPage::ConfigurationDescriptor inst_cfg_descriptors[] =
 {
-  ret.push_back (new EditorOptionsInst (root));
+  edt::RecentConfigurationPage::ConfigurationDescriptor (cfg_edit_inst_lib_name, tl::to_string (tr ("Library")), edt::RecentConfigurationPage::CellLibraryName),
+  edt::RecentConfigurationPage::ConfigurationDescriptor (cfg_edit_inst_cell_name, tl::to_string (tr ("Cell")), edt::RecentConfigurationPage::CellDisplayName),
+  edt::RecentConfigurationPage::ConfigurationDescriptor (cfg_edit_inst_angle, tl::to_string (tr ("Angle")), edt::RecentConfigurationPage::Double),
+  edt::RecentConfigurationPage::ConfigurationDescriptor (cfg_edit_inst_mirror, tl::to_string (tr ("Mirror")), edt::RecentConfigurationPage::Bool),
+  edt::RecentConfigurationPage::ConfigurationDescriptor (cfg_edit_inst_scale, tl::to_string (tr ("Scale")), edt::RecentConfigurationPage::Double),
+  edt::RecentConfigurationPage::ConfigurationDescriptor (cfg_edit_inst_array, tl::to_string (tr ("Array")), edt::RecentConfigurationPage::ArrayFlag),
+  edt::RecentConfigurationPage::ConfigurationDescriptor (cfg_edit_inst_rows, tl::to_string (tr ("Rows")), edt::RecentConfigurationPage::IntIfArray),
+  edt::RecentConfigurationPage::ConfigurationDescriptor (cfg_edit_inst_row_x, tl::to_string (tr ("Row step (x)")), edt::RecentConfigurationPage::DoubleIfArray),
+  edt::RecentConfigurationPage::ConfigurationDescriptor (cfg_edit_inst_row_y, tl::to_string (tr ("Row step (y)")), edt::RecentConfigurationPage::DoubleIfArray),
+  edt::RecentConfigurationPage::ConfigurationDescriptor (cfg_edit_inst_columns, tl::to_string (tr ("Columns")), edt::RecentConfigurationPage::IntIfArray),
+  edt::RecentConfigurationPage::ConfigurationDescriptor (cfg_edit_inst_column_x, tl::to_string (tr ("Column step (x)")), edt::RecentConfigurationPage::DoubleIfArray),
+  edt::RecentConfigurationPage::ConfigurationDescriptor (cfg_edit_inst_column_y, tl::to_string (tr ("Column step (y)")), edt::RecentConfigurationPage::DoubleIfArray),
+  edt::RecentConfigurationPage::ConfigurationDescriptor (cfg_edit_inst_pcell_parameters, tl::to_string (tr ("PCell parameters")), edt::RecentConfigurationPage::PCellParameters)
+};
+
+static
+void get_inst_editor_options_pages (std::vector<lay::EditorOptionsPage *> &ret, lay::LayoutView *view, lay::Dispatcher *dispatcher)
+{
+  ret.push_back (new RecentConfigurationPage (view, dispatcher, "edit-recent-inst-param",
+                        &inst_cfg_descriptors[0], &inst_cfg_descriptors[sizeof (inst_cfg_descriptors) / sizeof (inst_cfg_descriptors[0])]));
+  ret.push_back (new EditorOptionsInstPCellParam (dispatcher));
+  ret.push_back (new EditorOptionsInst (dispatcher));
 }
 
 template <class Svc>
@@ -97,7 +156,7 @@ class PluginDeclaration
 public:
   PluginDeclaration (const std::string &title, const std::string &mouse_mode, 
                      void (*option_get_f) (std::vector < std::pair<std::string, std::string> > &) = 0,
-                     void (*pages_f) (std::vector <edt::EditorOptionsPage *> &, lay::Dispatcher *) = 0)
+                     void (*pages_f) (std::vector <lay::EditorOptionsPage *> &, lay::LayoutView *, lay::Dispatcher *) = 0)
     : m_title (title), m_mouse_mode (mouse_mode), mp_option_get_f (option_get_f), mp_pages_f (pages_f)
   {
     //  .. nothing yet ..
@@ -120,11 +179,11 @@ public:
     //  .. nothing yet ..
   }
 
-  virtual void get_editor_options_pages (std::vector<edt::EditorOptionsPage *> &pages, lay::Dispatcher *root) const
+  virtual void get_editor_options_pages (std::vector<lay::EditorOptionsPage *> &pages, lay::LayoutView *view, lay::Dispatcher *root) const
   {
     if (mp_pages_f != 0) {
       size_t nstart = pages.size ();
-      (*mp_pages_f) (pages, root);
+      (*mp_pages_f) (pages, view, root);
       while (nstart < pages.size ()) {
         pages [nstart++]->set_plugin_declaration (this);
       }
@@ -155,16 +214,16 @@ private:
   std::string m_mouse_mode;
 
   void (*mp_option_get_f) (std::vector < std::pair<std::string, std::string> > &options);
-  void (*mp_pages_f) (std::vector <edt::EditorOptionsPage *> &, lay::Dispatcher *);
+  void (*mp_pages_f) (std::vector <lay::EditorOptionsPage *> &, lay::LayoutView *, lay::Dispatcher *);
 };
 
 static tl::RegisteredClass<lay::PluginDeclaration> config_decl1 (
-  new edt::PluginDeclaration<edt::PolygonService> (tl::to_string (QObject::tr ("Polygons")), "polygon:edit_mode\t" + tl::to_string (QObject::tr ("Polygon")) + "<:polygon.png>" + tl::to_string (QObject::tr ("{Create a polygon}"))), 
+  new edt::PluginDeclaration<edt::PolygonService> (tl::to_string (QObject::tr ("Polygons")), "polygon:edit_mode\t" + tl::to_string (QObject::tr ("Polygon")) + "<:polygon.png>" + tl::to_string (QObject::tr ("{Create a polygon}")), 0, &get_shape_editor_options_pages),
   4010, 
   "edt::Service(Polygons)"
 );
 static tl::RegisteredClass<lay::PluginDeclaration> config_decl2 (
-  new edt::PluginDeclaration<edt::BoxService> (tl::to_string (QObject::tr ("Boxes")), "box:edit_mode\t" + tl::to_string (QObject::tr ("Box")) + "\t<:box.png>" + tl::to_string (QObject::tr ("{Create a box}"))), 
+  new edt::PluginDeclaration<edt::BoxService> (tl::to_string (QObject::tr ("Boxes")), "box:edit_mode\t" + tl::to_string (QObject::tr ("Box")) + "\t<:box.png>" + tl::to_string (QObject::tr ("{Create a box}")), 0, &get_shape_editor_options_pages),
   4011, 
   "edt::Service(Boxes)"
 );
@@ -189,7 +248,7 @@ class MainPluginDeclaration
 {
 public:
   MainPluginDeclaration (const std::string &title)
-    : mp_root (0), m_title (title), mp_obj_prop_dialog (0)
+    : mp_root (0), m_title (title)
   {
     //  .. nothing yet ..
   }
@@ -218,13 +277,12 @@ public:
     menu_entries.push_back (lay::menu_item ("edt::descend", "descend", "zoom_menu.end", tl::to_string (QObject::tr ("Descend")) + "(Ctrl+D)"));
     menu_entries.push_back (lay::menu_item ("edt::ascend", "ascend", "zoom_menu.end", tl::to_string (QObject::tr ("Ascend")) + "(Ctrl+A)"));
 
-    menu_entries.push_back (lay::separator ("edit_options_group:edit_mode", "edit_menu.end"));
-    menu_entries.push_back (lay::menu_item ("edt::edit_options", "edit_options:edit_mode", "edit_menu.end", tl::to_string (QObject::tr ("Editor Options")) + "(F3)"));
     menu_entries.push_back (lay::menu_item ("edt::sel_make_array", "make_array:edit_mode", "edit_menu.selection_menu.end", tl::to_string (QObject::tr ("Make Array"))));
     menu_entries.push_back (lay::separator ("selection_group:edit_mode", "edit_menu.selection_menu.end"));
     menu_entries.push_back (lay::menu_item ("edt::sel_change_layer", "change_layer:edit_mode", "edit_menu.selection_menu.end", tl::to_string (QObject::tr ("Change Layer"))));
     menu_entries.push_back (lay::menu_item ("edt::sel_tap", "tap:edit_mode", "edit_menu.selection_menu.end", tl::to_string (QObject::tr ("Tap")) + "(T)"));
     menu_entries.push_back (lay::menu_item ("edt::sel_align", "align:edit_mode", "edit_menu.selection_menu.end", tl::to_string (QObject::tr ("Align"))));
+    menu_entries.push_back (lay::menu_item ("edt::sel_distribute", "distribute:edit_mode", "edit_menu.selection_menu.end", tl::to_string (QObject::tr ("Distribute"))));
     menu_entries.push_back (lay::menu_item ("edt::sel_round_corners", "round_corners:edit_mode", "edit_menu.selection_menu.end", tl::to_string (QObject::tr ("Round Corners"))));
     menu_entries.push_back (lay::menu_item ("edt::sel_size", "size:edit_mode", "edit_menu.selection_menu.end", tl::to_string (QObject::tr ("Size Shapes"))));
     menu_entries.push_back (lay::menu_item ("edt::sel_union", "union:edit_mode", "edit_menu.selection_menu.end", tl::to_string (QObject::tr ("Merge Shapes"))));
@@ -263,12 +321,19 @@ public:
   {
     return false;
   }
-  
+
   virtual bool implements_mouse_mode (std::string & /*title*/) const
   {
     return false;
   }
 
+  virtual void get_editor_options_pages (std::vector<lay::EditorOptionsPage *> &pages, lay::LayoutView * /*view*/, lay::Dispatcher *dispatcher) const
+  {
+    //  NOTE: we do not set plugin_declaration which makes the page unspecific
+    EditorOptionsGeneric *generic_opt = new EditorOptionsGeneric (dispatcher);
+    pages.push_back (generic_opt);
+  }
+
   virtual void initialize (lay::Dispatcher *root)
   {
     lay::Dispatcher *mp = lay::Dispatcher::instance ();
@@ -278,24 +343,6 @@ public:
 
     mp_root = root;
 
-    //  create the editor options dialog
-    m_prop_dialog_pages.push_back (new edt::EditorOptionsGeneric ());
-
-    for (tl::Registrar<lay::PluginDeclaration>::iterator cls = tl::Registrar<lay::PluginDeclaration>::begin (); cls != tl::Registrar<lay::PluginDeclaration>::end (); ++cls) {
-      const PluginDeclarationBase *pd_base = dynamic_cast<const PluginDeclarationBase *> (&*cls);
-      if (pd_base) {
-        pd_base->get_editor_options_pages (m_prop_dialog_pages, root);
-      }
-    }
-
-    mp_obj_prop_dialog = new edt::EditorOptionsPages (m_prop_dialog_pages, root);
-
-    for (std::vector<edt::EditorOptionsPage *>::const_iterator op = m_prop_dialog_pages.begin (); op != m_prop_dialog_pages.end (); ++op) {
-      if ((*op)->plugin_declaration () != 0) {
-        (*op)->activate (false);
-      }
-    }
-
     //  add entries to the combine mode dialog
     mp->menu ()->insert_item ("@toolbar.combine_mode.end", "combine_mode_add",   new lay::ConfigureAction (tl::to_string (QObject::tr ("Add<:/cm_add.png>{Add shapes}")),   cfg_edit_combine_mode, CMConverter ().to_string (CM_Add)));
     mp->menu ()->insert_item ("@toolbar.combine_mode.end", "combine_mode_merge", new lay::ConfigureAction (tl::to_string (QObject::tr ("Merge<:/cm_merge.png>{Merge shapes with background}")), cfg_edit_combine_mode, CMConverter ().to_string (CM_Merge)));
@@ -333,42 +380,6 @@ public:
     }
   }
 
-  virtual void uninitialize (lay::Dispatcher *)
-  {
-    if (mp_obj_prop_dialog) {
-      delete mp_obj_prop_dialog;
-      mp_obj_prop_dialog = 0;
-    }
-  }
-
-  virtual void config_finalize ()
-  {
-    if (mp_obj_prop_dialog && mp_obj_prop_dialog->isVisible ()) {
-      mp_obj_prop_dialog->setup ();
-    }
-  }
-
-  void show_dialog () const
-  {
-    if (mp_obj_prop_dialog) {
-      if (! mp_obj_prop_dialog->isVisible ()) {
-        mp_obj_prop_dialog->setup ();
-        mp_obj_prop_dialog->show ();
-      }
-      mp_obj_prop_dialog->activateWindow ();
-      mp_obj_prop_dialog->raise ();
-    }
-  }
-
-  void activate (const lay::PluginDeclaration *pd, bool active) const
-  {
-    for (std::vector<edt::EditorOptionsPage *>::const_iterator op = m_prop_dialog_pages.begin (); op != m_prop_dialog_pages.end (); ++op) {
-      if ((*op)->plugin_declaration () == pd) {
-        (*op)->activate (active);
-      }
-    }
-  }
-
   void initialized (lay::Dispatcher *root)
   {
     lay::Dispatcher *mp = lay::Dispatcher::instance ();
@@ -397,40 +408,27 @@ public:
 private:
   lay::Dispatcher *mp_root;
   std::string m_title;
-  edt::EditorOptionsPages *mp_obj_prop_dialog;
-  std::vector<edt::EditorOptionsPage *> m_prop_dialog_pages;
 };
 
+static tl::RegisteredClass<lay::PluginDeclaration> config_decl_main (new edt::MainPluginDeclaration (tl::to_string (QObject::tr ("Instances and shapes"))), 4000, "edt::MainService");
+
 void
-show_editor_options_dialog ()
+commit_recent (lay::LayoutView *view)
 {
-  //  look for the plugin declaration and show the dialog
-  for (tl::Registrar<lay::PluginDeclaration>::iterator cls = tl::Registrar<lay::PluginDeclaration>::begin (); cls != tl::Registrar<lay::PluginDeclaration>::end (); ++cls) {
-    const MainPluginDeclaration *main_pd = dynamic_cast<const MainPluginDeclaration *> (&*cls);
-    if (main_pd) {
-      main_pd->show_dialog ();
-      break;
+  lay::EditorOptionsPages *eo_pages = view->editor_options_pages ();;
+  if (!eo_pages) {
+    return;
+  }
+
+  for (std::vector<lay::EditorOptionsPage *>::const_iterator op = eo_pages->pages ().begin (); op != eo_pages->pages ().end (); ++op) {
+    if ((*op)->active ()) {
+      (*op)->commit_recent (view);
     }
   }
 }
 
-void 
-activate_service (const lay::PluginDeclaration *pd, bool active)
-{
-  //  look for the plugin declaration and show the dialog
-  for (tl::Registrar<lay::PluginDeclaration>::iterator cls = tl::Registrar<lay::PluginDeclaration>::begin (); cls != tl::Registrar<lay::PluginDeclaration>::end (); ++cls) {
-    const MainPluginDeclaration *main_pd = dynamic_cast<const MainPluginDeclaration *> (&*cls);
-    if (main_pd) {
-      main_pd->activate (pd, active);
-      break;
-    }
-  }
-}
-
-static tl::RegisteredClass<lay::PluginDeclaration> config_decl20 (new edt::MainPluginDeclaration (tl::to_string (QObject::tr ("Instances and shapes"))), 4000, "edt::MainService");
-
 class PartialPluginDeclaration
-  : public lay::PluginDeclaration
+  : public PluginDeclarationBase
 {
 public:
   PartialPluginDeclaration (const std::string &title, const std::string &mouse_mode)
@@ -444,6 +442,11 @@ public:
     //  .. nothing yet ..
   }
 
+  virtual void get_editor_options_pages (std::vector<lay::EditorOptionsPage *> & /*pages*/, lay::LayoutView * /*view*/, lay::Dispatcher * /*root*/) const
+  {
+    //  .. no specific ones ..
+  }
+
   virtual lay::Plugin *create_plugin (db::Manager *manager, lay::Dispatcher *root, lay::LayoutView *view) const
   {
     return new edt::PartialService (manager, view, root);
diff --git a/src/edt/edt/edtPlugin.h b/src/edt/edt/edtPlugin.h
index f75dec8dd..17dcd2389 100644
--- a/src/edt/edt/edtPlugin.h
+++ b/src/edt/edt/edtPlugin.h
@@ -31,35 +31,24 @@
 namespace lay
 {
   class Dispatcher;
+  class EditorOptionsPage;
 }
 
 namespace edt
 {
-  class EditorOptionsPage;
-
   /**
    *  @brief A helper class for plugin declarations for editor services
    */
   class PluginDeclarationBase
     : public lay::PluginDeclaration
   {
-  public:
-    virtual void get_editor_options_pages (std::vector<edt::EditorOptionsPage *> &, lay::Dispatcher *) const = 0;
+    //  .. nothing yet ..
   };
 
   /**
-   *  @brief Show the editor options dialog
-   *
-   *  This dialog is a global resource which is managed by the main plugin declaration
+   *  @brief Commits the current configuration for the recently used configuration list
    */
-  void show_editor_options_dialog ();
-
-  /**
-   *  @brief Activate or deactivate a certain service
-   *
-   *  This will show or hide the editor properties pages for the respective service.
-   */
-  void activate_service (const lay::PluginDeclaration *pd, bool active);
+  void commit_recent (lay::LayoutView *view);
 }
 
 #endif
diff --git a/src/edt/edt/edtPropertiesPageUtils.cc b/src/edt/edt/edtPropertiesPageUtils.cc
index 1bb1c9477..62fe988dc 100644
--- a/src/edt/edt/edtPropertiesPageUtils.cc
+++ b/src/edt/edt/edtPropertiesPageUtils.cc
@@ -26,6 +26,8 @@
 #include "dbShapes.h"
 #include "dbLayout.h"
 
+#include <QLineEdit>
+
 namespace edt
 {
 
diff --git a/src/edt/edt/edtPropertiesPageUtils.h b/src/edt/edt/edtPropertiesPageUtils.h
index fc43c71ae..1e71ff5cd 100644
--- a/src/edt/edt/edtPropertiesPageUtils.h
+++ b/src/edt/edt/edtPropertiesPageUtils.h
@@ -33,6 +33,8 @@
 
 #include <vector>
 
+class QLineEdit;
+
 namespace edt
 {
 
diff --git a/src/edt/edt/edtPropertiesPages.cc b/src/edt/edt/edtPropertiesPages.cc
index 8250241bb..ca645bcec 100644
--- a/src/edt/edt/edtPropertiesPages.cc
+++ b/src/edt/edt/edtPropertiesPages.cc
@@ -24,9 +24,11 @@
 #include "edtPropertiesPages.h"
 #include "edtPropertiesPageUtils.h"
 #include "edtDialogs.h"
+#include "edtPropertiesPageUtils.h"
 #include "layDialogs.h"
 #include "layObjectInstPath.h"
 #include "layLayoutView.h"
+#include "layQtTools.h"
 #include "tlExceptions.h"
 #include "tlString.h"
 
@@ -174,7 +176,7 @@ ShapePropertiesPage::recompute_selection_ptrs (const std::vector<lay::ObjectInst
 }
 
 void 
-ShapePropertiesPage::do_apply (bool current_only)
+ShapePropertiesPage::do_apply (bool current_only, bool relative)
 {
   std::auto_ptr<ChangeApplicator> applicator;
 
@@ -203,32 +205,7 @@ ShapePropertiesPage::do_apply (bool current_only)
   //  Ask whether to use relative or absolute mode
   bool relative_mode = false;
   if (! current_only && applicator->supports_relative_mode ()) {
-
-    static bool s_relative_mode = true;
-
-    QMessageBox mb (QMessageBox::Question, 
-                    tr ("Apply Changes To All"), 
-                    tr ("For this operation absolute or relative mode is available which affects the way parameters of the selected objects are changed:\n\n"
-                        "In absolute mode, they will be set to the given value. In relative mode, they will be adjusted by the same amount.\n"),
-                    QMessageBox::NoButton, this);
-
-    mb.addButton (tr ("Cancel"), QMessageBox::RejectRole);
-    QPushButton *absolute = mb.addButton (tr ("Absolute"), QMessageBox::NoRole);
-    QPushButton *relative = mb.addButton (tr ("Relative"), QMessageBox::YesRole);
-    
-    mb.setDefaultButton (s_relative_mode ? relative : absolute);
-
-    mb.exec ();
-
-    if (mb.clickedButton () == absolute) {
-      s_relative_mode = relative_mode = false;
-    } else if (mb.clickedButton () == relative) {
-      s_relative_mode = relative_mode = true;
-    } else {
-      //  Cancel pressed
-      return;
-    }
-
+    relative_mode = relative;
   }
 
   //  Note: using the apply-all scheme for applying a single change may look like overhead.
@@ -333,7 +310,7 @@ ShapePropertiesPage::do_apply (bool current_only)
 void 
 ShapePropertiesPage::apply ()
 {
-  do_apply (true);
+  do_apply (true, false);
 }
 
 bool
@@ -343,9 +320,9 @@ ShapePropertiesPage::can_apply_to_all () const
 }
 
 void 
-ShapePropertiesPage::apply_to_all ()
+ShapePropertiesPage::apply_to_all (bool relative)
 {
-  do_apply (false);
+  do_apply (false, relative);
 }
 
 void 
@@ -391,7 +368,9 @@ void
 ShapePropertiesPage::show_props ()
 {
   lay::UserPropertiesForm props_form (this);
-  props_form.show (mp_service->view (), m_selection_ptrs [m_index]->cv_index (), m_prop_id);
+  if (props_form.show (mp_service->view (), m_selection_ptrs [m_index]->cv_index (), m_prop_id)) {
+    emit edited ();
+  }
 }
 
 bool 
@@ -404,13 +383,19 @@ ShapePropertiesPage::readonly ()
 //  PolygonPropertiesPage implementation
 
 PolygonPropertiesPage::PolygonPropertiesPage (edt::Service *service, db::Manager *manager, QWidget *parent)
-  : ShapePropertiesPage (service, manager, parent)
+  : ShapePropertiesPage (service, manager, parent), m_in_text_changed (false)
 {
   setupUi (this);
   setup ();
 
   connect (inst_pb, SIGNAL (clicked ()), this, SLOT (show_inst ()));
   connect (prop_pb, SIGNAL (clicked ()), this, SLOT (show_props ()));
+
+  if (! readonly ()) {
+    connect (pointListEdit, SIGNAL (textChanged ()), this, SLOT (text_changed ()));
+  } else {
+    pointListEdit->setReadOnly (true);
+  }
 }
 
 void 
@@ -448,61 +433,87 @@ PolygonPropertiesPage::do_update (const db::Shape &shape, double dbu, const std:
 
   }
 
-  pointListEdit->setText (tl::to_qstring (ptlist));
+  if (! m_in_text_changed) {
+    pointListEdit->blockSignals (true);
+    pointListEdit->setText (tl::to_qstring (ptlist));
+    pointListEdit->blockSignals (false);
+  }
+
   pointCountLabel->setText (tl::to_qstring (tl::sprintf (tl::to_string (QObject::tr ("(%lu points)")), poly.vertices ())));
 }
 
+void
+PolygonPropertiesPage::text_changed ()
+{
+  m_in_text_changed = true;
+  try {
+    emit edited ();
+  } catch (tl::Exception &) {
+    //  ignore exceptions
+  }
+  m_in_text_changed = false;
+}
+
 ChangeApplicator *
 PolygonPropertiesPage::create_applicator (db::Shapes & /*shapes*/, const db::Shape &shape, double dbu)
 {
-  std::string text (tl::to_string (pointListEdit->toPlainText ()));
-  tl::Extractor ex (text.c_str ());
-
-  db::VCplxTrans t = db::CplxTrans (trans ()).inverted ();
-  bool du = dbu_units ();
-
   db::Polygon poly;
 
-  if (*ex.skip () == '(') {
+  try {
 
-    db::DPolygon dp;
-    ex.read (dp);
+    std::string text (tl::to_string (pointListEdit->toPlainText ()));
+    tl::Extractor ex (text.c_str ());
 
-    poly = db::Polygon (dp.transformed (db::DCplxTrans (t) * db::DCplxTrans (du ? 1.0 : 1.0 / dbu)));
+    db::VCplxTrans t = db::CplxTrans (trans ()).inverted ();
+    bool du = dbu_units ();
 
-  } else {
+    if (*ex.skip () == '(') {
 
-    unsigned int h = 0;
-    while (! ex.at_end ()) {
+      db::DPolygon dp;
+      ex.read (dp);
 
-      std::vector <db::Point> points;
+      poly = db::Polygon (dp.transformed (db::DCplxTrans (t) * db::DCplxTrans (du ? 1.0 : 1.0 / dbu)));
 
-      while (! ex.at_end () && ! ex.test ("/")) {
+    } else {
 
-        double dx = 0.0, dy = 0.0;
-        ex.read (dx);
-        ex.test (",");
-        ex.read (dy);
-        ex.test (";");
+      unsigned int h = 0;
+      while (! ex.at_end ()) {
 
-        points.push_back (point_from_dpoint (db::DPoint (dx, dy), dbu, du, t));
+        std::vector <db::Point> points;
+
+        while (! ex.at_end () && ! ex.test ("/")) {
+
+          double dx = 0.0, dy = 0.0;
+          ex.read (dx);
+          ex.test (",");
+          ex.read (dy);
+          ex.test (";");
+
+          points.push_back (point_from_dpoint (db::DPoint (dx, dy), dbu, du, t));
+
+        }
+
+        if (points.size () < 3) {
+          throw tl::Exception (tl::to_string (QObject::tr ("Polygon must have at least three points")));
+        }
+
+        if (h == 0) {
+          poly.assign_hull (points.begin (), points.end (), false /*not compressed*/);
+        } else {
+          poly.insert_hole (points.begin (), points.end (), false /*not compressed*/);
+        }
+
+        ++h;
 
       }
 
-      if (points.size () < 3) {
-        throw tl::Exception (tl::to_string (QObject::tr ("Polygon must have at least three points")));
-      }
-
-      if (h == 0) {
-        poly.assign_hull (points.begin (), points.end (), false /*not compressed*/);
-      } else {
-        poly.insert_hole (points.begin (), points.end (), false /*not compressed*/);
-      }
-
-      ++h;
-
     }
 
+    lay::indicate_error (pointListEdit, 0);
+
+  } catch (tl::Exception &ex) {
+    lay::indicate_error (pointListEdit, &ex);
+    throw;
   }
 
   db::Polygon org_poly;
@@ -525,15 +536,32 @@ BoxPropertiesPage::BoxPropertiesPage (edt::Service *service, db::Manager *manage
   setup ();
 
   mode_tab->setCurrentIndex (s_coordinateMode ? 0 : 1);
-  connect (mode_tab, SIGNAL (currentChanged (int)), this, SLOT (changed ()));
-  connect (x1_le_1, SIGNAL (editingFinished ()), this, SLOT (changed ()));
-  connect (y1_le_1, SIGNAL (editingFinished ()), this, SLOT (changed ()));
-  connect (x2_le_1, SIGNAL (editingFinished ()), this, SLOT (changed ()));
-  connect (y2_le_1, SIGNAL (editingFinished ()), this, SLOT (changed ()));
-  connect (w_le_2, SIGNAL (editingFinished ()), this, SLOT (changed ()));
-  connect (h_le_2, SIGNAL (editingFinished ()), this, SLOT (changed ()));
-  connect (cx_le_2, SIGNAL (editingFinished ()), this, SLOT (changed ()));
-  connect (cy_le_2, SIGNAL (editingFinished ()), this, SLOT (changed ()));
+
+  if (! readonly ()) {
+
+    connect (mode_tab, SIGNAL (currentChanged (int)), this, SLOT (changed ()));
+    connect (x1_le_1, SIGNAL (editingFinished ()), this, SLOT (changed ()));
+    connect (y1_le_1, SIGNAL (editingFinished ()), this, SLOT (changed ()));
+    connect (x2_le_1, SIGNAL (editingFinished ()), this, SLOT (changed ()));
+    connect (y2_le_1, SIGNAL (editingFinished ()), this, SLOT (changed ()));
+    connect (w_le_2, SIGNAL (editingFinished ()), this, SLOT (changed ()));
+    connect (h_le_2, SIGNAL (editingFinished ()), this, SLOT (changed ()));
+    connect (cx_le_2, SIGNAL (editingFinished ()), this, SLOT (changed ()));
+    connect (cy_le_2, SIGNAL (editingFinished ()), this, SLOT (changed ()));
+
+  } else {
+
+    x1_le_1->setReadOnly (true);
+    y1_le_1->setReadOnly (true);
+    x2_le_1->setReadOnly (true);
+    y2_le_1->setReadOnly (true);
+    w_le_2->setReadOnly (true);
+    h_le_2->setReadOnly (true);
+    cx_le_2->setReadOnly (true);
+    cy_le_2->setReadOnly (true);
+
+  }
+
   connect (inst_pb, SIGNAL (clicked ()), this, SLOT (show_inst ()));
   connect (prop_pb, SIGNAL (clicked ()), this, SLOT (show_props ()));
 }
@@ -576,11 +604,44 @@ BoxPropertiesPage::get_box (int mode) const
 {
   if (mode == 0) {
 
+    bool has_error = false;
     double x1 = 0.0, y1 = 0.0, x2 = 0.0, y2 = 0.0;
-    tl::from_string (tl::to_string (x1_le_1->text ()), x1);
-    tl::from_string (tl::to_string (y1_le_1->text ()), y1);
-    tl::from_string (tl::to_string (x2_le_1->text ()), x2);
-    tl::from_string (tl::to_string (y2_le_1->text ()), y2);
+
+    try {
+      tl::from_string (tl::to_string (x1_le_1->text ()), x1);
+      lay::indicate_error (x1_le_1, 0);
+    } catch (tl::Exception &ex) {
+      lay::indicate_error (x1_le_1, &ex);
+      has_error = true;
+    }
+
+    try {
+      tl::from_string (tl::to_string (y1_le_1->text ()), y1);
+      lay::indicate_error (y1_le_1, 0);
+    } catch (tl::Exception &ex) {
+      lay::indicate_error (y1_le_1, &ex);
+      has_error = true;
+    }
+
+    try {
+      tl::from_string (tl::to_string (x2_le_1->text ()), x2);
+      lay::indicate_error (x2_le_1, 0);
+    } catch (tl::Exception &ex) {
+      lay::indicate_error (x2_le_1, &ex);
+      has_error = true;
+    }
+
+    try {
+      tl::from_string (tl::to_string (y2_le_1->text ()), y2);
+      lay::indicate_error (y2_le_1, 0);
+    } catch (tl::Exception &ex) {
+      lay::indicate_error (y2_le_1, &ex);
+      has_error = true;
+    }
+
+    if (has_error) {
+      throw tl::Exception (tl::to_string (tr ("Invalid values - see highlighted entry boxes")));
+    }
 
     if (m_lr_swapped) {
       std::swap (x1, x2);
@@ -603,11 +664,44 @@ BoxPropertiesPage::get_box (int mode) const
 
   } else {
 
+    bool has_error = false;
     double cx = 0.0, cy = 0.0, w = 0.0, h = 0.0;
-    tl::from_string (tl::to_string (cx_le_2->text ()), cx);
-    tl::from_string (tl::to_string (cy_le_2->text ()), cy);
-    tl::from_string (tl::to_string (w_le_2->text ()), w);
-    tl::from_string (tl::to_string (h_le_2->text ()), h);
+
+    try {
+      tl::from_string (tl::to_string (cx_le_2->text ()), cx);
+      lay::indicate_error (cx_le_2, 0);
+    } catch (tl::Exception &ex) {
+      lay::indicate_error (cx_le_2, &ex);
+      has_error = true;
+    }
+
+    try {
+      tl::from_string (tl::to_string (cy_le_2->text ()), cy);
+      lay::indicate_error (cy_le_2, 0);
+    } catch (tl::Exception &ex) {
+      lay::indicate_error (cy_le_2, &ex);
+      has_error = true;
+    }
+
+    try {
+      tl::from_string (tl::to_string (w_le_2->text ()), w);
+      lay::indicate_error (w_le_2, 0);
+    } catch (tl::Exception &ex) {
+      lay::indicate_error (w_le_2, &ex);
+      has_error = true;
+    }
+
+    try {
+      tl::from_string (tl::to_string (h_le_2->text ()), h);
+      lay::indicate_error (h_le_2, 0);
+    } catch (tl::Exception &ex) {
+      lay::indicate_error (h_le_2, &ex);
+      has_error = true;
+    }
+
+    if (has_error) {
+      throw tl::Exception (tl::to_string (tr ("Invalid values - see highlighted entry boxes")));
+    }
 
     db::VCplxTrans t = db::VCplxTrans (trans ().inverted ());
     bool du = dbu_units ();
@@ -664,6 +758,8 @@ BoxPropertiesPage::changed ()
     set_box (get_box (m_tab_index));
   } catch (...) {
   }
+
+  emit edited ();
 }
 
 // -------------------------------------------------------------------------
@@ -677,6 +773,28 @@ TextPropertiesPage::TextPropertiesPage (edt::Service *service, db::Manager *mana
 
   connect (inst_pb, SIGNAL (clicked ()), this, SLOT (show_inst ()));
   connect (prop_pb, SIGNAL (clicked ()), this, SLOT (show_props ()));
+
+  if (! readonly ()) {
+
+    connect (text_le, SIGNAL (editingFinished ()), this, SIGNAL (edited ()));
+    connect (x_le, SIGNAL (editingFinished ()), this, SIGNAL (edited ()));
+    connect (y_le, SIGNAL (editingFinished ()), this, SIGNAL (edited ()));
+    connect (size_le, SIGNAL (editingFinished ()), this, SIGNAL (edited ()));
+    connect (orient_cbx, SIGNAL (activated (int)), this, SIGNAL (edited ()));
+    connect (halign_cbx, SIGNAL (activated (int)), this, SIGNAL (edited ()));
+    connect (valign_cbx, SIGNAL (activated (int)), this, SIGNAL (edited ()));
+
+  } else {
+
+    text_le->setReadOnly (true);
+    x_le->setReadOnly (true);
+    y_le->setReadOnly (true);
+    size_le->setReadOnly (true);
+    orient_cbx->setEnabled (false);
+    halign_cbx->setEnabled (false);
+    valign_cbx->setEnabled (false);
+
+  }
 }
 
 void 
@@ -707,12 +825,28 @@ TextPropertiesPage::do_update (const db::Shape &shape, double dbu, const std::st
 ChangeApplicator *
 TextPropertiesPage::create_applicator (db::Shapes & /*shapes*/, const db::Shape &shape, double dbu)
 {
+  bool has_error = false;
+
   db::VCplxTrans t = db::CplxTrans (trans ()).inverted ();
   bool du = dbu_units ();
 
   double x = 0.0, y = 0.0;
-  tl::from_string (tl::to_string (x_le->text ()), x);
-  tl::from_string (tl::to_string (y_le->text ()), y);
+
+  try {
+    tl::from_string (tl::to_string (x_le->text ()), x);
+    lay::indicate_error (x_le, 0);
+  } catch (tl::Exception &ex) {
+    lay::indicate_error (x_le, &ex);
+    has_error = true;
+  }
+
+  try {
+    tl::from_string (tl::to_string (y_le->text ()), y);
+    lay::indicate_error (y_le, 0);
+  } catch (tl::Exception &ex) {
+    lay::indicate_error (y_le, &ex);
+    has_error = true;
+  }
 
   db::Vector tp = db::Vector (point_from_dpoint (db::DPoint (x, y), dbu, du, t));
   db::Trans tt (orient_cbx->currentIndex (), tp);
@@ -739,7 +873,13 @@ TextPropertiesPage::create_applicator (db::Shapes & /*shapes*/, const db::Shape
 
   db::Coord size = 0;
   if (! size_le->text ().isEmpty ()) {
-    size = coord_from_string (tl::to_string (size_le->text ()).c_str (), dbu, du, t);
+    try {
+      size = coord_from_string (tl::to_string (size_le->text ()).c_str (), dbu, du, t);
+      lay::indicate_error (size_le, 0);
+    } catch (tl::Exception &ex) {
+      lay::indicate_error (size_le, &ex);
+      has_error = true;
+    }
   }
   if (size != org_text.size ()) {
     appl->add (new TextSizeChangeApplicator (size));
@@ -749,6 +889,10 @@ TextPropertiesPage::create_applicator (db::Shapes & /*shapes*/, const db::Shape
     appl->add (new TextStringChangeApplicator (str));
   }
 
+  if (has_error) {
+    throw tl::Exception (tl::to_string (tr ("Invalid values - see highlighted entry boxes")));
+  }
+
   return appl.release ();
 }
 
@@ -756,16 +900,22 @@ TextPropertiesPage::create_applicator (db::Shapes & /*shapes*/, const db::Shape
 //  PathPropertiesPage implementation
 
 PathPropertiesPage::PathPropertiesPage (edt::Service *service, db::Manager *manager, QWidget *parent)
-  : ShapePropertiesPage (service, manager, parent)
+  : ShapePropertiesPage (service, manager, parent), m_in_text_changed (false)
 {
   setupUi (this);
   setup ();
 
   connect (inst_pb, SIGNAL (clicked ()), this, SLOT (show_inst ()));
   connect (prop_pb, SIGNAL (clicked ()), this, SLOT (show_props ()));
+
+  ptlist_le->setReadOnly (true);
+  width_le->setReadOnly (true);
+  start_ext_le->setReadOnly (true);
+  end_ext_le->setReadOnly (true);
+  round_cb->setEnabled (false);
 }
 
-void 
+void
 PathPropertiesPage::do_update (const db::Shape &shape, double dbu, const std::string &lname)
 {
   layer_lbl->setText (tl::to_qstring (lname));
@@ -788,7 +938,12 @@ PathPropertiesPage::do_update (const db::Shape &shape, double dbu, const std::st
     }
     ptlist += coords_to_string (t * *pt, dbu, du);
   }
-  ptlist_le->setText (tl::to_qstring (ptlist));
+
+  if (! m_in_text_changed) {
+    ptlist_le->blockSignals (true);
+    ptlist_le->setText (tl::to_qstring (ptlist));
+    ptlist_le->blockSignals (false);
+  }
 
   width_le->setText (tl::to_qstring (coord_to_string (t.ctrans (path.width ()), dbu, du)));
   start_ext_le->setText (tl::to_qstring (coord_to_string (t.ctrans (path.extensions ().first), dbu, du)));
@@ -797,68 +952,16 @@ PathPropertiesPage::do_update (const db::Shape &shape, double dbu, const std::st
 }
 
 ChangeApplicator *
-PathPropertiesPage::create_applicator (db::Shapes & /*shapes*/, const db::Shape &shape, double dbu)
+PathPropertiesPage::create_applicator (db::Shapes & /*shapes*/, const db::Shape & /*shape*/, double /*dbu*/)
 {
-  db::VCplxTrans t = db::CplxTrans (trans ()).inverted ();
-  bool du = dbu_units ();
-
-  std::string text (tl::to_string (ptlist_le->toPlainText ()));
-  tl::Extractor ex (text.c_str ());
-
-  std::vector <db::Point> points;
-
-  while (! ex.at_end ()) {
-
-    double dx = 0.0, dy = 0.0;
-    ex.read (dx);
-    ex.read (dy);
-
-    points.push_back (point_from_dpoint (db::DPoint (dx, dy), dbu, du, t));
-
-  }
-
-  if (points.size () < 1) {
-    throw tl::Exception (tl::to_string (QObject::tr ("The path must have at least one point")));
-  }
-
-  db::Coord w = coord_from_string (tl::to_string (width_le->text ()).c_str (), dbu, du, t);
-  db::Coord se = coord_from_string (tl::to_string (start_ext_le->text ()).c_str (), dbu, du, t);
-  db::Coord ee = coord_from_string (tl::to_string (end_ext_le->text ()).c_str (), dbu, du, t);
-  bool round = round_cb->isChecked ();
-
-  std::auto_ptr<CombinedChangeApplicator> appl;
-
-  db::Path org_path;
-  shape.path (org_path);
-  std::vector <db::Point> org_points;
-  for (db::Path::iterator p = org_path.begin (); p != org_path.end (); ++p) {
-    org_points.push_back (*p);
-  }
-
-  if (org_points != points) {
-    appl->add (new PathPointsChangeApplicator (points, org_points));
-  }
-  if (w != org_path.width ()) {
-    appl->add (new PathWidthChangeApplicator (w, org_path.width ()));
-  }
-  if (se != org_path.extensions ().first) {
-    appl->add (new PathStartExtensionChangeApplicator (se));
-  }
-  if (ee != org_path.extensions ().second) {
-    appl->add (new PathEndExtensionChangeApplicator (ee));
-  }
-  if (round != org_path.round ()) {
-    appl->add (new PathRoundEndChangeApplicator (round));
-  }
-
-  return appl.release ();
+  return 0;
 }
 
 // -------------------------------------------------------------------------
 //  EditablePathPropertiesPage implementation
 
 EditablePathPropertiesPage::EditablePathPropertiesPage (edt::Service *service, db::Manager *manager, QWidget *parent)
-  : ShapePropertiesPage (service, manager, parent)
+  : ShapePropertiesPage (service, manager, parent), m_in_text_changed (false)
 {
   setupUi (this);
   setup ();
@@ -866,6 +969,12 @@ EditablePathPropertiesPage::EditablePathPropertiesPage (edt::Service *service, d
   connect (inst_pb, SIGNAL (clicked ()), this, SLOT (show_inst ()));
   connect (prop_pb, SIGNAL (clicked ()), this, SLOT (show_props ()));
   connect (type_cb, SIGNAL (currentIndexChanged (int)), this, SLOT (type_selected (int)));
+
+  connect (ptlist_le, SIGNAL (textChanged ()), this, SLOT (text_changed ()));
+  connect (width_le, SIGNAL (editingFinished ()), this, SIGNAL (edited ()));
+  connect (start_ext_le, SIGNAL (editingFinished ()), this, SIGNAL (edited ()));
+  connect (end_ext_le, SIGNAL (editingFinished ()), this, SIGNAL (edited ()));
+  connect (type_cb, SIGNAL (activated (int)), this, SIGNAL (edited ()));
 }
 
 static int 
@@ -886,7 +995,19 @@ path_type_choice (const db::Path &path)
   }
 }
 
-void 
+void
+EditablePathPropertiesPage::text_changed ()
+{
+  m_in_text_changed = true;
+  try {
+    emit edited ();
+  } catch (tl::Exception &) {
+    //  ignore exceptions
+  }
+  m_in_text_changed = false;
+}
+
+void
 EditablePathPropertiesPage::do_update (const db::Shape &shape, double dbu, const std::string &lname)
 {
   layer_lbl->setText (tl::to_qstring (lname));
@@ -909,7 +1030,12 @@ EditablePathPropertiesPage::do_update (const db::Shape &shape, double dbu, const
     }
     ptlist += coords_to_string (t * *pt, dbu, du);
   }
-  ptlist_le->setText (tl::to_qstring (ptlist));
+
+  if (! m_in_text_changed) {
+    ptlist_le->blockSignals (true);
+    ptlist_le->setText (tl::to_qstring (ptlist));
+    ptlist_le->blockSignals (false);
+  }
 
   db::Coord w = path.width ();
   db::Coord se = path.extensions ().first;
@@ -921,6 +1047,10 @@ EditablePathPropertiesPage::do_update (const db::Shape &shape, double dbu, const
   end_ext_le->setText (tl::to_qstring (coord_to_string (t.ctrans (ee), dbu, du)));
 
   int type_choice = path_type_choice (path);
+  if (type_cb->currentIndex () == 2) {
+    //  keep "variable" mode, otherwise if's difficult to switch to it
+    type_choice = 2;
+  }
   type_cb->setCurrentIndex (type_choice);
   type_selected (type_choice);
 }
@@ -928,6 +1058,8 @@ EditablePathPropertiesPage::do_update (const db::Shape &shape, double dbu, const
 ChangeApplicator *
 EditablePathPropertiesPage::create_applicator (db::Shapes & /*shapes*/, const db::Shape &shape, double dbu)
 {
+  bool has_error = false;
+
   db::VCplxTrans t = db::CplxTrans (trans ()).inverted ();
   bool du = dbu_units ();
 
@@ -936,22 +1068,38 @@ EditablePathPropertiesPage::create_applicator (db::Shapes & /*shapes*/, const db
 
   std::vector <db::Point> points;
 
-  while (! ex.at_end ()) {
+  try {
 
-    double dx = 0.0, dy = 0.0;
-    ex.read (dx);
-    ex.read (dy);
+    while (! ex.at_end ()) {
 
-    points.push_back (point_from_dpoint (db::DPoint (dx, dy), dbu, du, t));
+      double dx = 0.0, dy = 0.0;
+      ex.read (dx);
+      ex.read (dy);
 
+      points.push_back (point_from_dpoint (db::DPoint (dx, dy), dbu, du, t));
+
+    }
+
+    if (points.size () < 1) {
+      throw tl::Exception (tl::to_string (QObject::tr ("The path must have at least one point")));
+    }
+
+    lay::indicate_error (ptlist_le, 0);
+
+  } catch (tl::Exception &ex) {
+    lay::indicate_error (ptlist_le, &ex);
+    has_error = true;
   }
 
-  if (points.size () < 1) {
-    throw tl::Exception (tl::to_string (QObject::tr ("The path must have at least one point")));
+  db::Coord w = 0;
+  try {
+    w = coord_from_string (tl::to_string (width_le->text ()).c_str (), dbu, du, t);
+    lay::indicate_error (width_le, 0);
+  } catch (tl::Exception &ex) {
+    lay::indicate_error (width_le, &ex);
+    has_error = true;
   }
 
-  db::Coord w = coord_from_string (tl::to_string (width_le->text ()).c_str (), dbu, du, t);
-
   db::Coord se = 0, ee = 0;
   switch (type_cb->currentIndex ()) {
   case 0: // flush
@@ -961,8 +1109,20 @@ EditablePathPropertiesPage::create_applicator (db::Shapes & /*shapes*/, const db
     se = ee = std::numeric_limits <db::Coord>::min ();  //  force to half width
     break;
   case 2: // variable
-    se = coord_from_string (tl::to_string (start_ext_le->text ()).c_str (), dbu, du, t);
-    ee = coord_from_string (tl::to_string (end_ext_le->text ()).c_str (), dbu, du, t);
+    try {
+      se = coord_from_string (tl::to_string (start_ext_le->text ()).c_str (), dbu, du, t);
+      lay::indicate_error (start_ext_le, 0);
+    } catch (tl::Exception &ex) {
+      lay::indicate_error (start_ext_le, &ex);
+      has_error = true;
+    }
+    try {
+      ee = coord_from_string (tl::to_string (end_ext_le->text ()).c_str (), dbu, du, t);
+      lay::indicate_error (end_ext_le, 0);
+    } catch (tl::Exception &ex) {
+      lay::indicate_error (end_ext_le, &ex);
+      has_error = true;
+    }
     break;
   } 
 
@@ -989,6 +1149,10 @@ EditablePathPropertiesPage::create_applicator (db::Shapes & /*shapes*/, const db
     appl->add (new PathRoundEndChangeApplicator (type_cb->currentIndex () == 3));
   }
 
+  if (has_error) {
+    throw tl::Exception (tl::to_string (tr ("Invalid values - see highlighted entry boxes")));
+  }
+
   return appl.release ();
 }
 
diff --git a/src/edt/edt/edtPropertiesPages.h b/src/edt/edt/edtPropertiesPages.h
index 5b612326c..42e283cc2 100644
--- a/src/edt/edt/edtPropertiesPages.h
+++ b/src/edt/edt/edtPropertiesPages.h
@@ -56,13 +56,15 @@ public:
   virtual void operator++ ();
   virtual void leave ();
 
+protected:
+  virtual bool readonly ();
+
 private:
   virtual void update ();
   virtual void apply ();
-  virtual void apply_to_all ();
+  virtual void apply_to_all (bool relative);
   virtual bool can_apply_to_all () const;
-  virtual void do_apply (bool current_only);
-  virtual bool readonly ();
+  virtual void do_apply (bool current_only, bool relative);
   void recompute_selection_ptrs (const std::vector<lay::ObjectInstPath> &new_sel);
 
 protected:
@@ -104,6 +106,12 @@ public:
 protected:
   virtual QCheckBox *dbu_checkbox () const { return dbu_cb; }
   virtual QCheckBox *abs_checkbox () const { return abs_cb; }
+
+public slots:
+  void text_changed ();
+
+private:
+  bool m_in_text_changed;
 };
 
 class BoxPropertiesPage
@@ -167,6 +175,9 @@ public:
 protected:
   virtual QCheckBox *dbu_checkbox () const { return dbu_cb; }
   virtual QCheckBox *abs_checkbox () const { return abs_cb; }
+
+private:
+  bool m_in_text_changed;
 };
 
 class EditablePathPropertiesPage
@@ -187,6 +198,10 @@ protected:
 
 public slots:
   void type_selected (int); 
+  void text_changed ();
+
+private:
+  bool m_in_text_changed;
 };
 
 }
diff --git a/src/edt/edt/edtRecentConfigurationPage.cc b/src/edt/edt/edtRecentConfigurationPage.cc
new file mode 100644
index 000000000..554f85be0
--- /dev/null
+++ b/src/edt/edt/edtRecentConfigurationPage.cc
@@ -0,0 +1,394 @@
+
+/*
+
+  KLayout Layout Viewer
+  Copyright (C) 2006-2020 Matthias Koefferlein
+
+  This program is free software; you can redistribute it and/or modify
+  it under the terms of the GNU General Public License as published by
+  the Free Software Foundation; either version 2 of the License, or
+  (at your option) any later version.
+
+  This program is distributed in the hope that it will be useful,
+  but WITHOUT ANY WARRANTY; without even the implied warranty of
+  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+  GNU General Public License for more details.
+
+  You should have received a copy of the GNU General Public License
+  along with this program; if not, write to the Free Software
+  Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
+
+*/
+
+#include "edtRecentConfigurationPage.h"
+#include "edtUtils.h"
+#include "layDispatcher.h"
+#include "layLayoutView.h"
+#include "layLayerTreeModel.h"
+#include "dbLibraryManager.h"
+#include "dbLibrary.h"
+
+#include <QVBoxLayout>
+#include <QHeaderView>
+#include <QLabel>
+
+namespace edt
+{
+
+static const size_t max_entries = 100;
+
+void
+RecentConfigurationPage::init ()
+{
+  QVBoxLayout *ly = new QVBoxLayout (this);
+  ly->setMargin (0);
+
+  QLabel *label = new QLabel (this);
+  label->setText (tr ("Click to select a recent configuration"));
+  ly->addWidget (label);
+
+  mp_tree_widget = new QTreeWidget (this);
+  mp_tree_widget->setRootIsDecorated (false);
+  mp_tree_widget->setUniformRowHeights (true);
+  mp_tree_widget->setSelectionMode (QAbstractItemView::NoSelection);
+  mp_tree_widget->setAllColumnsShowFocus (true);
+  ly->addWidget (mp_tree_widget);
+
+  connect (mp_tree_widget, SIGNAL (itemClicked (QTreeWidgetItem *, int)), this, SLOT (item_clicked (QTreeWidgetItem *)));
+  mp_view->layer_list_changed_event.add (this, &RecentConfigurationPage::layers_changed);
+
+  mp_tree_widget->setColumnCount (int (m_cfg.size ()));
+
+  QStringList column_labels;
+  for (std::list<ConfigurationDescriptor>::const_iterator c = m_cfg.begin (); c != m_cfg.end (); ++c) {
+    column_labels << tl::to_qstring (c->title);
+  }
+  mp_tree_widget->setHeaderLabels (column_labels);
+
+  update_list (get_stored_values ());
+}
+
+RecentConfigurationPage::~RecentConfigurationPage ()
+{
+  //  .. nothing yet ..
+}
+
+std::string RecentConfigurationPage::title () const
+{
+  return tl::to_string (tr ("Recent"));
+}
+
+int RecentConfigurationPage::order () const
+{
+  return 100;
+}
+
+std::list<std::vector<std::string> >
+RecentConfigurationPage::get_stored_values () const
+{
+  std::string serialized_list = dispatcher ()->config_get (m_recent_cfg_name);
+
+  std::list<std::vector<std::string> > values;
+  tl::Extractor ex (serialized_list.c_str ());
+  while (! ex.at_end ()) {
+
+    values.push_back (std::vector<std::string> ());
+    while (! ex.at_end () && ! ex.test (";")) {
+      values.back ().push_back (std::string ());
+      ex.read_word_or_quoted (values.back ().back ());
+      ex.test (",");
+    }
+
+  }
+
+  return values;
+}
+
+void
+RecentConfigurationPage::set_stored_values (const std::list<std::vector<std::string> > &values) const
+{
+  std::string serialized_list;
+  for (std::list<std::vector<std::string> >::const_iterator v = values.begin (); v != values.end (); ++v) {
+    if (v != values.begin ()) {
+      serialized_list += ";";
+    }
+    for (std::vector<std::string>::const_iterator s = v->begin (); s != v->end (); ++s) {
+      serialized_list += tl::to_word_or_quoted_string (*s);
+      serialized_list += ",";
+    }
+  }
+
+  dispatcher ()->config_set (m_recent_cfg_name, serialized_list);
+}
+
+static lay::LayerPropertiesConstIterator
+lp_iter_from_string (lay::LayoutView *view, const std::string &s)
+{
+  //  parse the layer spec (<layer-props>[@<cv-index>])
+  db::LayerProperties lp;
+  tl::Extractor ex (s.c_str ());
+  lp.read (ex);
+  int cv_index = 0;
+  if (ex.test ("@")) {
+    ex.read (cv_index);
+  }
+
+  //  rename the ones that got shifted.
+  lay::LayerPropertiesConstIterator l = view->begin_layers ();
+  while (! l.at_end ()) {
+    if (l->source (true).cv_index () == int (cv_index) && l->source (true).layer_props ().log_equal (lp)) {
+      return l;
+    }
+    ++l;
+  }
+
+  return l;
+}
+
+
+void
+RecentConfigurationPage::render_to (QTreeWidgetItem *item, int column, const std::vector<std::string> &values, RecentConfigurationPage::ConfigurationRendering rendering)
+{
+  //  store original value
+  item->setData (column, Qt::UserRole, tl::to_qstring (values [column]));
+
+  switch (rendering) {
+
+  case RecentConfigurationPage::ArrayFlag:
+  case RecentConfigurationPage::Bool:
+    {
+      bool f = false;
+      tl::from_string (values [column], f);
+      static QString checkmark = QString::fromUtf8 ("\xe2\x9c\x93");
+      item->setText (column, f ? checkmark : QString ()); // "checkmark"
+    }
+    break;
+
+  case RecentConfigurationPage::Layer:
+    {
+      int icon_size = mp_view->style ()->pixelMetric (QStyle::PM_ButtonIconSize);
+      lay::LayerPropertiesConstIterator l = lp_iter_from_string (mp_view, values [column]);
+      if (! l.is_null () && ! l.at_end ()) {
+        item->setIcon (column, lay::LayerTreeModel::icon_for_layer (l, mp_view, icon_size, icon_size, 0, true));
+        item->setText (column, tl::to_qstring (values [column]));
+      } else {
+        item->setIcon (column, QIcon ());
+        item->setText (column, tl::to_qstring ("(" + values [column] + ")"));
+      }
+    }
+    break;
+
+  case RecentConfigurationPage::Int:
+  case RecentConfigurationPage::Double:
+  case RecentConfigurationPage::Text:
+    item->setText (column, tl::to_qstring (values [column]));
+    break;
+
+  case RecentConfigurationPage::CellLibraryName:
+    if (values [column].empty ()) {
+      item->setText (column, tr ("(local)"));
+    } else {
+      item->setText (column, tl::to_qstring (values [column]));
+    }
+    break;
+
+  case RecentConfigurationPage::IntIfArray:
+  case RecentConfigurationPage::DoubleIfArray:
+    {
+      bool is_array = false;
+      int flag_column = 0;
+      for (std::list<ConfigurationDescriptor>::const_iterator c = m_cfg.begin (); c != m_cfg.end (); ++c, ++flag_column) {
+        if (c->rendering == RecentConfigurationPage::ArrayFlag) {
+          tl::from_string (values [flag_column], is_array);
+          break;
+        }
+      }
+
+      if (is_array) {
+        item->setText (column, tl::to_qstring (values [column]));
+      } else {
+        item->setText (column, QString ());
+      }
+    }
+    break;
+
+  case RecentConfigurationPage::CellDisplayName:
+    {
+      //  search for a libname
+      int libname_column = 0;
+      const db::Library *lib = 0;
+      for (std::list<ConfigurationDescriptor>::const_iterator c = m_cfg.begin (); c != m_cfg.end (); ++c, ++libname_column) {
+        if (c->rendering == RecentConfigurationPage::CellLibraryName) {
+          lib = db::LibraryManager::instance ().lib_ptr_by_name (values [libname_column]);
+          break;
+        }
+      }
+
+      if (lib) {
+
+        //  search for a PCell parameters
+        int pcp_column = 0;
+        std::map<std::string, tl::Variant> pcp;
+        for (std::list<ConfigurationDescriptor>::const_iterator c = m_cfg.begin (); c != m_cfg.end (); ++c, ++pcp_column) {
+          if (c->rendering == RecentConfigurationPage::PCellParameters) {
+            pcp = pcell_parameters_from_string (values [pcp_column]);
+            break;
+          }
+        }
+
+        std::pair<bool, db::Layout::pcell_id_type> pcid = lib->layout ().pcell_by_name (values [column].c_str ());
+        if (pcid.first) {
+          const db::PCellDeclaration *pc_decl = lib->layout ().pcell_declaration (pcid.second);
+          if (pc_decl) {
+            item->setText (column, tl::to_qstring (pc_decl->get_display_name (pc_decl->map_parameters (pcp))));
+            break;
+          }
+        }
+
+      }
+
+      item->setText (column, tl::to_qstring (values [column]));
+    }
+    break;
+
+  case RecentConfigurationPage::PCellParameters:
+    {
+      std::map<std::string, tl::Variant> pcp;
+      pcp = pcell_parameters_from_string (values [column]);
+      std::string r;
+      for (std::map<std::string, tl::Variant>::const_iterator p = pcp.begin (); p != pcp.end (); ++p) {
+        if (p != pcp.begin ()) {
+          r += ",";
+        }
+        r += p->first;
+        r += "=";
+        r += p->second.to_string ();
+      }
+
+      item->setText (column, tl::to_qstring (r));
+    }
+    break;
+  }
+
+}
+
+void
+RecentConfigurationPage::layers_changed (int)
+{
+  update_list (get_stored_values ());
+}
+
+void
+RecentConfigurationPage::update_list (const std::list<std::vector<std::string> > &stored_values)
+{
+  int row = 0;
+  for (std::list<std::vector<std::string> >::const_iterator v = stored_values.begin (); v != stored_values.end (); ++v, ++row) {
+
+    QTreeWidgetItem *item = 0;
+    if (row < mp_tree_widget->topLevelItemCount ()) {
+      item = mp_tree_widget->topLevelItem (row);
+    } else {
+      item = new QTreeWidgetItem (mp_tree_widget);
+      mp_tree_widget->addTopLevelItem (item);
+    }
+
+    int column = 0;
+    for (std::list<ConfigurationDescriptor>::const_iterator c = m_cfg.begin (); c != m_cfg.end (); ++c, ++column) {
+      if (column < int (v->size ())) {
+        render_to (item, column, *v, c->rendering);
+      }
+    }
+
+  }
+
+  while (mp_tree_widget->topLevelItemCount () > row) {
+    delete mp_tree_widget->takeTopLevelItem (row);
+  }
+
+  mp_tree_widget->header ()->resizeSections (QHeaderView::ResizeToContents);
+}
+
+void
+RecentConfigurationPage::item_clicked (QTreeWidgetItem *item)
+{
+  int column = 0;
+  for (std::list<ConfigurationDescriptor>::const_iterator c = m_cfg.begin (); c != m_cfg.end (); ++c, ++column) {
+
+    std::string v = tl::to_string (item->data (column, Qt::UserRole).toString ());
+
+    if (c->rendering == Layer) {
+
+      //  "getting" a layer means making it current
+      db::LayerProperties lp;
+      tl::Extractor ex (v.c_str ());
+      lp.read (ex);
+      int cv_index = 0;
+      if (ex.test ("@")) {
+        ex.read (cv_index);
+      }
+
+      mp_view->set_or_request_current_layer (cv_index, lp);
+
+    } else {
+      dispatcher ()->config_set (c->cfg_name, v);
+    }
+
+  }
+
+  dispatcher ()->config_end ();
+}
+
+void
+RecentConfigurationPage::commit_recent (lay::Dispatcher *root)
+{
+  std::vector<std::string> values;
+  values.reserve (m_cfg.size ());
+  for (std::list<ConfigurationDescriptor>::const_iterator c = m_cfg.begin (); c != m_cfg.end (); ++c) {
+
+    if (c->rendering == Layer) {
+
+      std::string s;
+
+      if (!(mp_view->current_layer ().is_null () || mp_view->current_layer ().at_end ()) && mp_view->current_layer ()->is_visual ()) {
+
+        int cv_index = mp_view->current_layer ()->cellview_index ();
+        const lay::CellView &cv = mp_view->cellview (cv_index);
+        int li = mp_view->current_layer ()->layer_index ();
+        if (cv.is_valid () && cv->layout ().is_valid_layer (li)) {
+          s = cv->layout ().get_properties (li).to_string ();
+          if (cv_index > 0) {
+             s += "@" + tl::to_string (cv_index);
+          }
+        }
+
+      }
+
+      values.push_back (s);
+
+    } else {
+      values.push_back (root->config_get (c->cfg_name));
+    }
+
+  }
+
+  std::list<std::vector<std::string> > stored_values = get_stored_values ();
+
+  for (std::list<std::vector<std::string> >::iterator v = stored_values.begin (); v != stored_values.end (); ++v) {
+    if (*v == values) {
+      stored_values.erase (v);
+      break;
+    }
+  }
+
+  stored_values.push_front (values);
+
+  while (stored_values.size () > max_entries) {
+    stored_values.erase (--stored_values.end ());
+  }
+
+  set_stored_values (stored_values);
+
+  update_list (stored_values);
+}
+
+}
diff --git a/src/edt/edt/edtRecentConfigurationPage.h b/src/edt/edt/edtRecentConfigurationPage.h
new file mode 100644
index 000000000..a177be7fb
--- /dev/null
+++ b/src/edt/edt/edtRecentConfigurationPage.h
@@ -0,0 +1,115 @@
+
+/*
+
+  KLayout Layout Viewer
+  Copyright (C) 2006-2020 Matthias Koefferlein
+
+  This program is free software; you can redistribute it and/or modify
+  it under the terms of the GNU General Public License as published by
+  the Free Software Foundation; either version 2 of the License, or
+  (at your option) any later version.
+
+  This program is distributed in the hope that it will be useful,
+  but WITHOUT ANY WARRANTY; without even the implied warranty of
+  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+  GNU General Public License for more details.
+
+  You should have received a copy of the GNU General Public License
+  along with this program; if not, write to the Free Software
+  Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
+
+*/
+
+
+#ifndef HDR_edtRecentConfigurationPage
+#define HDR_edtRecentConfigurationPage
+
+#include "layEditorOptionsPage.h"
+#include "tlObject.h"
+
+#include <list>
+#include <QTreeWidget>
+
+namespace lay
+{
+  class LayoutView;
+}
+
+namespace edt
+{
+
+class PCellParametersPage;
+
+class EditorOptionsPages;
+
+/**
+ *  @brief The base class for a object properties page
+ */
+class RecentConfigurationPage
+  : public lay::EditorOptionsPage,
+    public tl::Object
+{
+Q_OBJECT
+
+public:
+  enum ConfigurationRendering
+  {
+    Text = 0,
+    Bool = 1,
+    Double = 2,
+    Int = 3,
+    Layer = 4,
+    PCellParameters = 5,
+    CellLibraryName = 6,
+    CellDisplayName = 7,
+    ArrayFlag = 8,
+    DoubleIfArray = 9,
+    IntIfArray = 10
+  };
+
+  struct ConfigurationDescriptor
+  {
+    ConfigurationDescriptor (const std::string &_cfg_name, const std::string &_title, ConfigurationRendering _rendering)
+      : cfg_name (_cfg_name), title (_title), rendering (_rendering)
+    { }
+
+    std::string cfg_name, title;
+    ConfigurationRendering rendering;
+  };
+
+  template <class Iter>
+  RecentConfigurationPage (lay::LayoutView *view, lay::Dispatcher *dispatcher, const std::string &recent_cfg_name, Iter begin_cfg, Iter end_cfg)
+    : EditorOptionsPage (dispatcher), mp_view (view), m_recent_cfg_name (recent_cfg_name), m_cfg (begin_cfg, end_cfg)
+  {
+    init ();
+  }
+
+  virtual ~RecentConfigurationPage ();
+
+  virtual std::string title () const;
+  virtual int order () const;
+  virtual void apply (lay::Dispatcher * /*root*/) { }
+  virtual void setup (lay::Dispatcher * /*root*/) { }
+  virtual void commit_recent (lay::Dispatcher *root);
+
+private slots:
+  void item_clicked (QTreeWidgetItem *item);
+
+private:
+  lay::LayoutView *mp_view;
+  std::string m_recent_cfg_name;
+  std::list<ConfigurationDescriptor> m_cfg;
+  QTreeWidget *mp_tree_widget;
+
+  void init ();
+  void update_list (const std::list<std::vector<std::string> > &stored_values);
+  std::list<std::vector<std::string> > get_stored_values () const;
+  void set_stored_values (const std::list<std::vector<std::string> > &values) const;
+  void render_to (QTreeWidgetItem *item, int column, const std::vector<std::string> &values, RecentConfigurationPage::ConfigurationRendering rendering);
+  void layers_changed (int);
+};
+
+}
+
+#endif
+
diff --git a/src/edt/edt/edtService.cc b/src/edt/edt/edtService.cc
index 0e5986b5c..904c91574 100644
--- a/src/edt/edt/edtService.cc
+++ b/src/edt/edt/edtService.cc
@@ -60,49 +60,8 @@ ac_from_buttons (unsigned int buttons)
 
 // -------------------------------------------------------------
 
-std::string pcell_parameters_to_string (const std::map<std::string, tl::Variant> &parameters)
-{
-  std::string param;
-
-  param = "!";  //  flags PCells
-  for (std::map<std::string, tl::Variant>::const_iterator p = parameters.begin (); p != parameters.end (); ++p) {
-    param += tl::to_word_or_quoted_string (p->first);
-    param += ":";
-    param += p->second.to_parsable_string ();
-    param += ";";
-  }
-
-  return param;
-}
-
-std::map<std::string, tl::Variant> pcell_parameters_from_string (const std::string &s)
-{
-  tl::Extractor ex (s.c_str ());
-  std::map<std::string, tl::Variant> pm;
-
-  ex.test ("!");
-
-  try {
-    while (! ex.at_end ()) {
-      std::string n;
-      ex.read_word_or_quoted (n);
-      ex.test (":");
-      ex.read (pm.insert (std::make_pair (n, tl::Variant ())).first->second);
-      ex.test (";");
-    }
-  } catch (...) {
-    //  ignore errors
-  }
-
-  return pm;
-}
-
-// -------------------------------------------------------------
-
 Service::Service (db::Manager *manager, lay::LayoutView *view, db::ShapeIterator::flags_type flags)
-  : lay::ViewService (view->view_object_widget ()), 
-    lay::Editable (view),
-    lay::Plugin (view),
+  : lay::EditorServiceBase (view),
     db::Object (manager),
     mp_view (view),
     mp_transient_marker (0), 
@@ -122,9 +81,7 @@ Service::Service (db::Manager *manager, lay::LayoutView *view, db::ShapeIterator
 }
 
 Service::Service (db::Manager *manager, lay::LayoutView *view)
-  : lay::ViewService (view->view_object_widget ()), 
-    lay::Editable (view),
-    lay::Plugin (view),
+  : lay::EditorServiceBase (view),
     db::Object (manager),
     mp_view (view),
     mp_transient_marker (0), 
@@ -217,18 +174,30 @@ Service::snap (const db::DPoint &p, const db::DPoint &plast, bool connect) const
 
 const int sr_pixels = 8; // TODO: make variable
 
-db::DPoint 
-Service::snap2 (const db::DPoint &p) const
+lay::PointSnapToObjectResult
+Service::snap2_details (const db::DPoint &p) const
 {
   double snap_range = widget ()->mouse_event_trans ().inverted ().ctrans (sr_pixels);
-  return lay::obj_snap (m_snap_to_objects ? view () : 0, p, m_edit_grid == db::DVector () ? m_global_grid : m_edit_grid, snap_range).second;
+  return lay::obj_snap (m_snap_to_objects ? view () : 0, p, m_edit_grid == db::DVector () ? m_global_grid : m_edit_grid, snap_range);
+}
+
+db::DPoint
+Service::snap2 (const db::DPoint &p) const
+{
+  return snap2_details (p).snapped_point;
 }
 
 db::DPoint 
 Service::snap2 (const db::DPoint &p, const db::DPoint &plast, bool connect) const
 {
   double snap_range = widget ()->mouse_event_trans ().inverted ().ctrans (sr_pixels);
-  return lay::obj_snap (m_snap_to_objects ? view () : 0, plast, p, m_edit_grid == db::DVector () ? m_global_grid : m_edit_grid, connect ? connect_ac () : move_ac (), snap_range).second;
+  return lay::obj_snap (m_snap_to_objects ? view () : 0, plast, p, m_edit_grid == db::DVector () ? m_global_grid : m_edit_grid, connect ? connect_ac () : move_ac (), snap_range).snapped_point;
+}
+
+void
+Service::service_configuration_changed ()
+{
+  //  The base class implementation does nothing
 }
 
 bool
@@ -238,27 +207,60 @@ Service::configure (const std::string &name, const std::string &value)
   edt::ACConverter acc;
 
   if (name == cfg_edit_global_grid) {
+
     egc.from_string (value, m_global_grid);
+    service_configuration_changed ();
+
   } else if (name == cfg_edit_show_shapes_of_instances) {
+
     tl::from_string (value, m_show_shapes_of_instances);
+    service_configuration_changed ();
+
   } else if (name == cfg_edit_max_shapes_of_instances) {
+
     tl::from_string (value, m_max_shapes_of_instances);
+    service_configuration_changed ();
+
   } else if (name == cfg_edit_grid) {
+
     egc.from_string (value, m_edit_grid);
+    service_configuration_changed ();
+
     return true;  //  taken
+
   } else if (name == cfg_edit_snap_to_objects) {
+
     tl::from_string (value, m_snap_to_objects);
+    service_configuration_changed ();
+
     return true;  //  taken
+
   } else if (name == cfg_edit_move_angle_mode) {
+
     acc.from_string (value, m_move_ac);
+    service_configuration_changed ();
+
     return true;  //  taken
+
   } else if (name == cfg_edit_connect_angle_mode) {
+
     acc.from_string (value, m_connect_ac);
+    service_configuration_changed ();
+
     return true;  //  taken
+
   } else if (name == cfg_edit_top_level_selection) {
+
     tl::from_string (value, m_top_level_sel);
+    service_configuration_changed ();
+
   } else if (name == cfg_edit_hier_copy_mode) {
+
     tl::from_string (value, m_hier_copy_mode);
+    service_configuration_changed ();
+
+  } else {
+    lay::EditorServiceBase::configure (name, value);
   }
 
   return false;  //  not taken
@@ -710,14 +712,15 @@ Service::mouse_move_event (const db::DPoint &p, unsigned int buttons, bool prio)
         //  in this mode, ignore exceptions here since it is rather annoying to have messages popping
         //  up then.
         try {
-          do_begin_edit (p);
-          m_editing = true;
+          begin_edit (p);
         } catch (...) {
           set_edit_marker (0);
         }
       }
       if (m_editing) {
         do_mouse_move (p);
+      } else {
+        do_mouse_move_inactive (p);
       }
 
       m_alt_ac = lay::AC_Global;
@@ -744,8 +747,7 @@ Service::mouse_press_event (const db::DPoint &p, unsigned int buttons, bool prio
 
         view ()->cancel ();  //  cancel any pending edit operations and clear the selection
         set_edit_marker (0);
-        do_begin_edit (p);
-        m_editing = true;
+        begin_edit (p);
 
       } else {
         if (do_mouse_click (p)) {
@@ -797,22 +799,21 @@ Service::mouse_click_event (const db::DPoint &p, unsigned int buttons, bool prio
 void
 Service::activated ()
 {
-  //  make all editor option pages visible
-  activate_service (plugin_declaration (), true);
-
   if (view ()->is_editable ()) {
+
     view ()->cancel ();  //  cancel any pending edit operations and clear the selection
     set_edit_marker (0);
+
     m_immediate = do_activated ();
     m_editing = false;
+
   }
 }
 
 void   
 Service::deactivated ()
 {
-  //  make all editor option pages visible
-  activate_service (plugin_declaration (), false);
+  lay::EditorServiceBase::deactivated ();
 
   edit_cancel ();
 
@@ -1432,6 +1433,19 @@ Service::move_markers (const db::DTrans &t)
   }
 }
 
+void
+Service::begin_edit (const db::DPoint &p)
+{
+  do_begin_edit (p);
+  m_editing = true;
+}
+
+void
+Service::tap (const db::DPoint & /*initial*/)
+{
+  //  .. nothing here ..
+}
+
 void 
 Service::selection_to_view ()
 {
diff --git a/src/edt/edt/edtService.h b/src/edt/edt/edtService.h
index cb4812f79..b24871cf6 100644
--- a/src/edt/edt/edtService.h
+++ b/src/edt/edt/edtService.h
@@ -27,9 +27,8 @@
 
 #include "edtCommon.h"
 
-#include "layEditable.h"
+#include "layEditorServiceBase.h"
 #include "layPlugin.h"
-#include "layViewObject.h"
 #include "layMarker.h"
 #include "laySnap.h"
 #include "layObjectInstPath.h"
@@ -44,12 +43,14 @@
 #include <vector>
 #include <QColor>
 
+namespace lay {
+  class LayerPropertiesConstIterator;
+}
+
 namespace edt {
 
 class Service;
 class PluginDeclarationBase;
-class EditorOptionsPages;
-class EditorOptionsPage;
 
 // -------------------------------------------------------------
 
@@ -70,9 +71,7 @@ std::map<std::string, tl::Variant> pcell_parameters_from_string (const std::stri
 // -------------------------------------------------------------
 
 class EDT_PUBLIC Service
-  : public lay::ViewService,
-    public lay::Editable,
-    public lay::Plugin,
+  : public lay::EditorServiceBase,
     public db::Object
 {
 public: 
@@ -216,22 +215,6 @@ public:
     return m_color;
   }
 
-  /**
-   *  @brief Obtain the lay::ViewService interface
-   */
-  lay::ViewService *view_service_interface ()
-  {
-    return this;
-  }
-
-  /**
-   *  @brief Obtain the lay::Editable interface
-   */
-  lay::Editable *editable_interface ()
-  {
-    return this;
-  }
-
   /**
    *  @brief Get the selection container
    */
@@ -344,6 +327,11 @@ public:
    */
   virtual void edit_cancel ();
 
+  /**
+   *  @brief Triggered by tap - gives the new layer and if required the initial point
+   */
+  virtual void tap (const db::DPoint &initial);
+
   /**
    *  @brief Delete the selected rulers
    *
@@ -383,6 +371,11 @@ protected:
    */
   void selection_to_view ();
 
+  /**
+   *  @brief starts editing at the given point.
+   */
+  void begin_edit (const db::DPoint &p);
+
   /**
    *  @brief Reimplemented by the specific implementation of the shape editors
    *
@@ -441,6 +434,11 @@ protected:
    */
   virtual void do_cancel_edit () { }
 
+  /**
+   *  @brief Called when a configuration parameter provided by the service base class has changed
+   */
+  virtual void service_configuration_changed ();
+
   /**
    *  @brief Install a marker for representing the edited object
    *
@@ -528,6 +526,16 @@ protected:
     return m_max_shapes_of_instances;
   }
 
+  bool editing () const
+  {
+    return m_editing;
+  }
+
+  /**
+   *  @brief Point snapping with detailed return value
+   */
+  lay::PointSnapToObjectResult snap2_details (const db::DPoint &p) const;
+
 private:
   //  The layout view that the editor service is attached to
   lay::LayoutView *mp_view;
diff --git a/src/edt/edt/edtServiceImpl.cc b/src/edt/edt/edtServiceImpl.cc
index 691bff357..c15bc6106 100644
--- a/src/edt/edt/edtServiceImpl.cc
+++ b/src/edt/edt/edtServiceImpl.cc
@@ -25,8 +25,8 @@
 #include "edtServiceImpl.h"
 #include "edtPropertiesPages.h"
 #include "edtInstPropertiesPage.h"
-#include "edtPCellParametersDialog.h"
 #include "edtService.h"
+#include "edtPlugin.h"
 #include "dbEdge.h"
 #include "dbLibrary.h"
 #include "dbLibraryManager.h"
@@ -51,7 +51,7 @@ ShapeEditService::ShapeEditService (db::Manager *manager, lay::LayoutView *view,
   : edt::Service (manager, view, shape_types), 
     m_layer (0), m_cv_index (0), mp_cell (0), mp_layout (0), m_combine_mode (CM_Add)
 {
-  //  .. nothing yet ..
+  view->current_layer_changed_event.add (this, &ShapeEditService::update_edit_layer);
 }
 
 bool 
@@ -69,17 +69,11 @@ void
 ShapeEditService::get_edit_layer ()
 {
   lay::LayerPropertiesConstIterator cl = view ()->current_layer ();
+
   if (cl.is_null ()) {
     throw tl::Exception (tl::to_string (QObject::tr ("Please select a layer first")));
   }
 
-  if (! cl->visible (true)) {
-    lay::TipDialog td (QApplication::activeWindow (),
-                       tl::to_string (QObject::tr ("You are about to draw on a hidden layer. The result won't be visible.")), 
-                       "drawing-on-invisible-layer");
-    td.exec_dialog ();
-  }
-  
   int cv_index = cl->cellview_index ();
   const lay::CellView &cv = view ()->cellview (cv_index);
   int layer = cl->layer_index ();
@@ -88,6 +82,13 @@ ShapeEditService::get_edit_layer ()
     throw tl::Exception (tl::to_string (QObject::tr ("Please select a cell first")));
   }
 
+  if (! cl->visible (true)) {
+    lay::TipDialog td (QApplication::activeWindow (),
+                       tl::to_string (QObject::tr ("You are about to draw on a hidden layer. The result won't be visible.")),
+                       "drawing-on-invisible-layer");
+    td.exec_dialog ();
+  }
+
   if (layer < 0 || ! cv->layout ().is_valid_layer ((unsigned int) layer)) {
 
     if (cl->has_children ()) {
@@ -128,6 +129,79 @@ ShapeEditService::get_edit_layer ()
   }
 }
 
+void
+ShapeEditService::update_edit_layer (const lay::LayerPropertiesConstIterator &cl)
+{
+  if (! editing ()) {
+    return;
+  }
+
+  if (cl.is_null () || cl->has_children ()) {
+    return;
+  }
+
+  int cv_index = cl->cellview_index ();
+  const lay::CellView &cv = view ()->cellview (cv_index);
+  int layer = cl->layer_index ();
+
+  if (cv_index < 0 || ! cv.is_valid ()) {
+    return;
+  }
+
+  if (cv->layout ().cell (cv.cell_index ()).is_proxy ()) {
+    return;
+  }
+
+  if (! cl->visible (true)) {
+    lay::TipDialog td (QApplication::activeWindow (),
+                       tl::to_string (QObject::tr ("You are now drawing on a hidden layer. The result won't be visible.")),
+                       "drawing-on-invisible-layer");
+    td.exec_dialog ();
+  }
+
+  if (layer < 0 || ! cv->layout ().is_valid_layer ((unsigned int) layer)) {
+
+    //  create this layer now
+    const lay::ParsedLayerSource &source = cl->source (true /*real*/);
+
+    db::LayerProperties db_lp;
+    if (source.has_name ()) {
+      db_lp.name = source.name ();
+    }
+    db_lp.layer = source.layer ();
+    db_lp.datatype = source.datatype ();
+
+    cv->layout ().insert_layer (db_lp);
+
+    //  update the layer index inside the layer view
+    cl->realize_source ();
+
+    //  Hint: we could have taken the new index from insert_layer, but this
+    //  is a nice test:
+    layer = cl->layer_index ();
+    tl_assert (layer >= 0);
+
+  }
+
+  m_layer = (unsigned int) layer;
+  m_cv_index = (unsigned int) cv_index;
+  m_trans = (cl->trans ().front () * db::CplxTrans (cv->layout ().dbu ()) * cv.context_trans ()).inverted ();
+  mp_layout = &(cv->layout ());
+  mp_cell = &(mp_layout->cell (cv.cell_index ()));
+
+  current_layer_changed ();
+}
+
+void
+ShapeEditService::tap (const db::DPoint &initial)
+{
+  if (editing ()) {
+    get_edit_layer ();
+  } else {
+    begin_edit (initial);
+  }
+}
+
 /**
  *  @brief Deliver a good interpolation between two points m and p
  *
@@ -339,9 +413,18 @@ PolygonService::set_last_point (const db::DPoint &p)
   }
 }
 
-void 
+void
+PolygonService::do_mouse_move_inactive (const db::DPoint &p)
+{
+  lay::PointSnapToObjectResult snap_details = snap2_details (p);
+  mouse_cursor_from_snap_details (snap_details);
+}
+
+void
 PolygonService::do_mouse_move (const db::DPoint &p)
 {
+  do_mouse_move_inactive (p);
+
   set_cursor (lay::Cursor::cross);
   if (m_points.size () >= 2) {
     set_last_point (p);
@@ -366,6 +449,7 @@ void
 PolygonService::do_finish_edit ()
 {
   deliver_shape (get_polygon ());
+  commit_recent (view ());
 }
 
 db::Polygon
@@ -644,9 +728,18 @@ BoxService::update_marker ()
   }
 }
 
-void 
+void
+BoxService::do_mouse_move_inactive (const db::DPoint &p)
+{
+  lay::PointSnapToObjectResult snap_details = snap2_details (p);
+  mouse_cursor_from_snap_details (snap_details);
+}
+
+void
 BoxService::do_mouse_move (const db::DPoint &p)
 {
+  do_mouse_move_inactive (p);
+
   set_cursor (lay::Cursor::cross);
   m_p2 = snap2 (p);
   update_marker ();
@@ -663,6 +756,7 @@ void
 BoxService::do_finish_edit ()
 {
   deliver_shape (get_box ());
+  commit_recent (view ());
 }
 
 void 
@@ -738,18 +832,21 @@ TextService::do_activated ()
 {
   m_rot = 0;
 
-  //  Show editor options dialog to allow entering of width
-  std::vector<edt::MainService *> edt_main_services = view ()->get_plugins <edt::MainService> ();
-  if (edt_main_services.size () > 0) {
-    edt_main_services [0]->cm_edit_options ();
-  }
-
   return true;  //  start editing immediately
 }
 
-void 
+void
+TextService::do_mouse_move_inactive (const db::DPoint &p)
+{
+  lay::PointSnapToObjectResult snap_details = snap2_details (p);
+  mouse_cursor_from_snap_details (snap_details);
+}
+
+void
 TextService::do_mouse_move (const db::DPoint &p)
 {
+  do_mouse_move_inactive (p);
+
   set_cursor (lay::Cursor::cross);
   m_text.trans (db::DTrans (m_rot, snap2 (p) - db::DPoint ()));
   update_marker ();
@@ -786,6 +883,8 @@ TextService::do_finish_edit ()
   cell ().shapes (layer ()).insert (get_text ());
   manager ()->commit ();
 
+  commit_recent (view ());
+
   if (! view ()->text_visible ()) {
 
     lay::TipDialog td (QApplication::activeWindow (),
@@ -904,12 +1003,6 @@ PathService::do_begin_edit (const db::DPoint &p)
 bool
 PathService::do_activated ()
 {
-  //  Show editor options dialog to allow entering of width
-  std::vector<edt::MainService *> edt_main_services = view ()->get_plugins <edt::MainService> ();
-  if (edt_main_services.size () > 0) {
-    edt_main_services [0]->cm_edit_options ();
-  }
-
   return false;  //  don't start editing immediately
 }
 
@@ -935,9 +1028,18 @@ PathService::set_last_point (const db::DPoint &p)
   }
 }
 
-void 
+void
+PathService::do_mouse_move_inactive (const db::DPoint &p)
+{
+  lay::PointSnapToObjectResult snap_details = snap2_details (p);
+  mouse_cursor_from_snap_details (snap_details);
+}
+
+void
 PathService::do_mouse_move (const db::DPoint &p)
 {
+  do_mouse_move_inactive (p);
+
   set_cursor (lay::Cursor::cross);
   if (m_points.size () >= 2) {
     set_last_point (p);
@@ -966,6 +1068,8 @@ PathService::do_finish_edit ()
   m_points.pop_back ();
 
   deliver_shape (get_path ());
+
+  commit_recent (view ());
 }
 
 void
@@ -1094,7 +1198,7 @@ InstService::InstService (db::Manager *manager, lay::LayoutView *view)
     m_array (false), m_rows (1), m_columns (1), 
     m_row_x (0.0), m_row_y (0.0), m_column_x (0.0), m_column_y (0.0),
     m_place_origin (false), m_reference_transaction_id (0),
-    m_needs_update (true), m_has_valid_cell (false), m_in_drag_drop (false), 
+    m_needs_update (true), m_parameters_changed (false), m_has_valid_cell (false), m_in_drag_drop (false),
     m_current_cell (0), mp_current_layout (0), mp_pcell_decl (0), m_cv_index (-1)
 { 
   //  .. nothing yet ..
@@ -1109,12 +1213,6 @@ InstService::properties_page (db::Manager *manager, QWidget *parent)
 bool
 InstService::do_activated ()
 {
-  //  Show editor options dialog to allow entering of parameters
-  std::vector<edt::MainService *> edt_main_services = view ()->get_plugins <edt::MainService> ();
-  if (edt_main_services.size () > 0) {
-    edt_main_services [0]->cm_edit_options ();
-  }
-
   m_cv_index = view ()->active_cellview_index ();
   m_has_valid_cell = false;
 
@@ -1137,63 +1235,69 @@ InstService::get_default_layer_for_pcell ()
 
 bool
 InstService::drag_enter_event (const db::DPoint &p, const lay::DragDropDataBase *data)
-{ 
+{
   const lay::CellDragDropData *cd = dynamic_cast <const lay::CellDragDropData *> (data);
   if (view ()->is_editable () && cd && (cd->layout () == & view ()->active_cellview ()->layout () || cd->library ())) {
 
     view ()->cancel ();
-
     set_edit_marker (0);
 
-    m_cv_index = view ()->active_cellview_index ();
-    m_in_drag_drop = true;
+    bool switch_parameters = true;
 
+    //  configure from the drag/drop data
     if (cd->library ()) {
+
+      //  Reject drag & drop if the target technology does not match
+      if (cd->library ()->for_technologies () && view ()->cellview (view ()->active_cellview_index ()).is_valid ()) {
+        if (! cd->library ()->is_for_technology (view ()->cellview (view ()->active_cellview_index ())->tech_name ())) {
+          return false;
+        }
+      }
+
       if (m_lib_name != cd->library ()->get_name ()) {
         m_lib_name = cd->library ()->get_name ();
-        m_pcell_parameters.clear ();
       }
+
     } else {
       m_lib_name.clear ();
     }
 
-    m_is_pcell = false;
-
     if (cd->is_pcell ()) {
 
       const db::PCellDeclaration *pcell_decl = cd->layout ()->pcell_declaration (cd->cell_index ());
-      if (pcell_decl) {
+      if (! pcell_decl) {
+        return false;
+      }
 
-        if (m_cell_or_pcell_name != pcell_decl->name ()) {
-          m_cell_or_pcell_name = pcell_decl->name ();
-          m_pcell_parameters.clear ();
-        }
-
-        m_is_pcell = true;
-
-        //  NOTE: we reuse previous parameters for convenience unless PCell or library has changed
-        const std::vector<db::PCellParameterDeclaration> &pd = pcell_decl->parameter_declarations();
-        for (std::vector<db::PCellParameterDeclaration>::const_iterator i = pd.begin (); i != pd.end (); ++i) {
-          if (i->get_type () == db::PCellParameterDeclaration::t_layer && !i->is_hidden () && !i->is_readonly () && i->get_default ().is_nil ()) {
-            m_pcell_parameters.insert (std::make_pair (i->get_name (), get_default_layer_for_pcell ()));
-          } else {
-            m_pcell_parameters.insert (std::make_pair (i->get_name (), i->get_default ()));
-          }
-        }
-
-        do_begin_edit (p);
-        return true;
+      if (m_cell_or_pcell_name != pcell_decl->name ()) {
+        m_cell_or_pcell_name = pcell_decl->name ();
+      }
 
+      if (! cd->pcell_params ().empty ()) {
+        m_pcell_parameters = pcell_decl->named_parameters (cd->pcell_params ());
+        switch_parameters = false;
       }
 
     } else if (cd->layout ()->is_valid_cell_index (cd->cell_index ())) {
 
       m_cell_or_pcell_name = cd->layout ()->cell_name (cd->cell_index ());
-      do_begin_edit (p);
-      return true;
 
+    } else {
+      return false;
     }
 
+    switch_cell_or_pcell (switch_parameters);
+
+    sync_to_config ();
+    m_in_drag_drop = true;
+
+    view ()->switch_mode (plugin_declaration ()->id ());
+
+    do_begin_edit (p);
+
+    //  action taken.
+    return true;
+
   }
 
   return false;
@@ -1210,7 +1314,7 @@ InstService::drag_move_event (const db::DPoint &p, const lay::DragDropDataBase *
   }
 }
 
-void  
+void
 InstService::drag_leave_event () 
 { 
   if (m_in_drag_drop) {
@@ -1219,7 +1323,7 @@ InstService::drag_leave_event ()
   }
 }
 
-bool 
+bool
 InstService::selection_applies (const lay::ObjectInstPath &sel) const
 {
   return sel.is_cell_inst ();
@@ -1228,53 +1332,8 @@ InstService::selection_applies (const lay::ObjectInstPath &sel) const
 bool  
 InstService::drop_event (const db::DPoint & /*p*/, const lay::DragDropDataBase * /*data*/) 
 { 
-  if (m_in_drag_drop) {
-
-    const lay::CellView &cv = view ()->cellview (m_cv_index);
-    if (! cv.is_valid ()) {
-      return false;
-    }
-
-    make_cell (cv);
-
-    bool accepted = true;
-
-    if (m_has_valid_cell && mp_pcell_decl) {
-
-      std::vector<tl::Variant> pv = mp_pcell_decl->map_parameters (m_pcell_parameters);
-
-      //  Turn off the drag cursor for the modal dialog
-      QApplication::restoreOverrideCursor ();
-
-      //  for PCells dragged show the parameter dialog for a chance to edit the initial parameters
-      if (! mp_pcell_parameters_dialog.get ()) {
-        mp_pcell_parameters_dialog.reset (new edt::PCellParametersDialog (view ()));
-        mp_pcell_parameters_dialog->parameters_changed_event.add (this, &InstService::apply_edits);
-      }
-
-      if (! mp_pcell_parameters_dialog->exec (mp_current_layout, view (), m_cv_index, mp_pcell_decl, pv)) {
-        accepted = false;
-      } else {
-        m_has_valid_cell = false;
-        m_pcell_parameters = mp_pcell_decl->named_parameters (mp_pcell_parameters_dialog->get_parameters ());
-      }
-
-    }
-
-    set_edit_marker (0);
-
-    if (accepted) {
-      do_finish_edit ();
-    } else {
-      do_cancel_edit ();
-    }
-
-    sync_to_config ();
-    return true;
-
-  } else {
-    return false; 
-  }
+  m_in_drag_drop = false;
+  return false;
 }
 
 void
@@ -1337,10 +1396,6 @@ InstService::do_begin_edit (const db::DPoint &p)
     m_trans = db::VCplxTrans (1.0 / cv->layout ().dbu ()) * tv [0] * db::CplxTrans (cv->layout ().dbu ()) * cv.context_trans ();
   }
 
-  lay::Marker *marker = new lay::Marker (view (), m_cv_index, ! show_shapes_of_instances (), show_shapes_of_instances () ? max_shapes_of_instances () : 0);
-  marker->set_vertex_shape (lay::ViewOp::Cross);
-  marker->set_vertex_size (9 /*cross vertex size*/);
-  set_edit_marker (marker);
   update_marker ();
 }
 
@@ -1426,9 +1481,18 @@ InstService::make_cell (const lay::CellView &cv)
   return std::pair<bool, db::cell_index_type> (true, inst_cell_index);
 }
 
-void 
+void
+InstService::do_mouse_move_inactive (const db::DPoint &p)
+{
+  clear_mouse_cursors ();
+  add_mouse_cursor (snap (p));
+}
+
+void
 InstService::do_mouse_move (const db::DPoint &p)
 {
+  do_mouse_move_inactive (p);
+
   set_cursor (lay::Cursor::cross);
 
   const lay::CellView &cv = view ()->cellview (m_cv_index);
@@ -1470,6 +1534,14 @@ InstService::do_mouse_transform (const db::DPoint &p, db::DFTrans trans)
   m_column_x = c.x ();
   m_column_y = c.y ();
 
+  dispatcher ()->config_set (cfg_edit_inst_angle, m_angle);
+  dispatcher ()->config_set (cfg_edit_inst_mirror, m_mirror);
+  dispatcher ()->config_set (cfg_edit_inst_row_x, m_row_x);
+  dispatcher ()->config_set (cfg_edit_inst_row_y, m_row_y);
+  dispatcher ()->config_set (cfg_edit_inst_column_x, m_column_x);
+  dispatcher ()->config_set (cfg_edit_inst_column_y, m_column_y);
+  dispatcher ()->config_end ();
+
   //  honour the new transformation
   do_mouse_move (p);
 }
@@ -1510,6 +1582,8 @@ InstService::do_finish_edit ()
       cv->layout ().cleanup ();
       manager ()->commit ();
 
+      commit_recent (view ());
+
       if (m_in_drag_drop) {
 
         lay::ObjectInstPath sel;
@@ -1545,6 +1619,8 @@ InstService::do_cancel_edit ()
   m_has_valid_cell = false;
   m_in_drag_drop = false;
 
+  set_edit_marker (0);
+
   //  clean up any proxy cells created so far 
   const lay::CellView &cv = view ()->cellview (m_cv_index);
   if (cv.is_valid ()) {
@@ -1552,132 +1628,307 @@ InstService::do_cancel_edit ()
   }
 }
 
+void
+InstService::service_configuration_changed ()
+{
+  m_needs_update = true;
+}
+
 bool 
 InstService::configure (const std::string &name, const std::string &value)
 {
   if (name == cfg_edit_inst_cell_name) {
-    m_cell_or_pcell_name = value;
-    m_needs_update = true;
+
+    if (value != m_cell_or_pcell_name) {
+      m_cell_or_pcell_name = value;
+      m_needs_update = true;
+    }
+
     return true; // taken
   }
 
   if (name == cfg_edit_inst_lib_name) {
-    m_lib_name = value;
-    m_needs_update = true;
+
+    if (value != m_lib_name) {
+      m_lib_name_previous = m_lib_name;
+      m_lib_name = value;
+      m_needs_update = true;
+    }
+
     return true; // taken
   }
 
   if (name == cfg_edit_inst_pcell_parameters) {
 
-    m_pcell_parameters = pcell_parameters_from_string (value);
-    m_is_pcell = ! value.empty ();
+    std::map<std::string, tl::Variant> pcp = pcell_parameters_from_string (value);
+    if (pcp != m_pcell_parameters) {
+
+      m_pcell_parameters = pcp;
+      m_is_pcell = ! value.empty ();
+
+      m_needs_update = true;
+      m_parameters_changed = true;
+
+    }
 
-    m_needs_update = true;
     return true; // taken
 
   }
 
   if (name == cfg_edit_inst_place_origin) {
-    tl::from_string (value, m_place_origin);
-    m_needs_update = true;
+
+    bool f;
+    tl::from_string (value, f);
+
+    if (f != m_place_origin) {
+      m_place_origin = f;
+      m_needs_update = true;
+    }
+
     return true; // taken
+
   }
 
   if (name == cfg_edit_inst_scale) {
-    tl::from_string (value, m_scale);
-    m_needs_update = true;
+
+    double s;
+    tl::from_string (value, s);
+
+    if (fabs (s - m_scale) > 1e-10) {
+      m_scale = s;
+      m_needs_update = true;
+    }
+
     return true; // taken
+
   }
 
   if (name == cfg_edit_inst_angle) {
-    tl::from_string (value, m_angle);
-    m_needs_update = true;
+
+    double a;
+    tl::from_string (value, a);
+
+    if (fabs (a - m_angle) > 1e-10) {
+      m_angle = a;
+      m_needs_update = true;
+    }
+
     return true; // taken
   }
 
   if (name == cfg_edit_inst_mirror) {
-    tl::from_string (value, m_mirror);
-    m_needs_update = true;
+
+    bool f;
+    tl::from_string (value, f);
+
+    if (f != m_mirror) {
+      m_mirror = f;
+      m_needs_update = true;
+    }
+
     return true; // taken
+
   }
 
   if (name == cfg_edit_inst_array) {
-    tl::from_string (value, m_array);
-    m_needs_update = true;
+
+    bool f;
+    tl::from_string (value, f);
+
+    if (f != m_array) {
+      m_array = f;
+      m_needs_update = true;
+    }
+
     return true; // taken
+
   }
 
   if (name == cfg_edit_inst_rows) {
-    tl::from_string (value, m_rows);
-    m_needs_update = true;
+
+    unsigned int v;
+    tl::from_string (value, v);
+
+    if (v != m_rows) {
+      m_rows = v;
+      m_needs_update = true;
+    }
+
     return true; // taken
+
   }
 
   if (name == cfg_edit_inst_row_x) {
-    tl::from_string (value, m_row_x);
-    m_needs_update = true;
+
+    double v;
+    tl::from_string (value, v);
+
+    if (! db::coord_traits<double>::equal (m_row_x, v)) {
+      m_row_x = v;
+      m_needs_update = true;
+    }
+
     return true; // taken
+
   }
 
   if (name == cfg_edit_inst_row_y) {
-    tl::from_string (value, m_row_y);
-    m_needs_update = true;
+
+    double v;
+    tl::from_string (value, v);
+
+    if (! db::coord_traits<double>::equal (m_row_y, v)) {
+      m_row_y = v;
+      m_needs_update = true;
+    }
+
     return true; // taken
+
   }
 
   if (name == cfg_edit_inst_columns) {
-    tl::from_string (value, m_columns);
-    m_needs_update = true;
+
+    unsigned int v;
+    tl::from_string (value, v);
+
+    if (v != m_columns) {
+      m_columns = v;
+      m_needs_update = true;
+    }
+
     return true; // taken
+
   }
 
   if (name == cfg_edit_inst_column_x) {
-    tl::from_string (value, m_column_x);
-    m_needs_update = true;
+
+    double v;
+    tl::from_string (value, v);
+
+    if (! db::coord_traits<double>::equal (m_column_x, v)) {
+      m_column_x = v;
+      m_needs_update = true;
+    }
+
     return true; // taken
+
   }
 
   if (name == cfg_edit_inst_column_y) {
-    tl::from_string (value, m_column_y);
-    m_needs_update = true;
+
+    double v;
+    tl::from_string (value, v);
+
+    if (! db::coord_traits<double>::equal (m_column_y, v)) {
+      m_column_y = v;
+      m_needs_update = true;
+    }
+
     return true; // taken
+
   }
 
   return edt::Service::configure (name, value);
 }
 
+void
+InstService::switch_cell_or_pcell (bool switch_parameters)
+{
+  //  if the library or cell name has changed, store the current pcell parameters and try to reuse
+  //  an existing parameter set
+  if (! m_cell_or_pcell_name_previous.empty () && (m_cell_or_pcell_name_previous != m_cell_or_pcell_name || m_lib_name_previous != m_lib_name)) {
+
+    m_stored_pcell_parameters[std::make_pair (m_cell_or_pcell_name_previous, m_lib_name_previous)] = m_pcell_parameters;
+
+    if (switch_parameters) {
+
+      std::map<std::pair<std::string, std::string>, std::map<std::string, tl::Variant> >::const_iterator p = m_stored_pcell_parameters.find (std::make_pair (m_cell_or_pcell_name, m_lib_name));
+      if (p != m_stored_pcell_parameters.end ()) {
+        m_pcell_parameters = p->second;
+      } else {
+        m_pcell_parameters.clear ();
+      }
+
+    }
+
+  }
+
+  db::Library *lib = db::LibraryManager::instance ().lib_ptr_by_name (m_lib_name);
+  const lay::CellView &cv = view ()->cellview (m_cv_index);
+
+  //  find the layout the cell has to be looked up: that is either the layout of the current instance or
+  //  the library selected
+  const db::Layout *layout = 0;
+  if (lib) {
+    layout = &lib->layout ();
+  } else if (cv.is_valid ()) {
+    layout = &cv->layout ();
+  }
+
+  if (layout) {
+    m_is_pcell = layout->pcell_by_name (m_cell_or_pcell_name.c_str ()).first;
+  } else {
+    m_is_pcell = false;
+  }
+
+  //  remember the current cell or library name
+  m_cell_or_pcell_name_previous = m_cell_or_pcell_name;
+  m_lib_name_previous = m_lib_name;
+}
+
 void 
 InstService::config_finalize ()
 {
   if (m_needs_update) {
+
+    //  don't switch parameters if they have been updated explicitly
+    //  since the last "config_finalize". This means the sender of the configuration events
+    //  wants the parameters to be set in a specific way. Don't interfere.
+    bool switch_parameters = ! m_parameters_changed;
+
+    switch_cell_or_pcell (switch_parameters);
+
     m_has_valid_cell = false;
     update_marker ();
-    m_needs_update = false;
+
+    if (switch_parameters) {
+      //  Reflects any changes in PCell parameters in the configuration
+      //  TODO: it's somewhat questionable to do this inside "config_finalize" as this method is supposed
+      //  to reflect changes rather than induce some.
+      if (m_is_pcell) {
+        dispatcher ()->config_set (cfg_edit_inst_pcell_parameters, pcell_parameters_to_string (m_pcell_parameters));
+      } else {
+        dispatcher ()->config_set (cfg_edit_inst_pcell_parameters, std::string ());
+      }
+    }
+
   }
 
+  m_needs_update = false;
+  m_parameters_changed = false;
+
   edt::Service::config_finalize ();
 }
 
-void
-InstService::apply_edits()
-{
-  if (mp_pcell_decl && mp_pcell_parameters_dialog.get ()) {
-    m_pcell_parameters = mp_pcell_decl->named_parameters (mp_pcell_parameters_dialog->get_parameters ());
-  }
-
-  sync_to_config ();
-}
-
 void
 InstService::update_marker ()
 {
-  lay::Marker *marker = dynamic_cast<lay::Marker *> (edit_marker ());
-  if (marker) {
-    marker->set ();
+  if (editing ()) {
+
+    lay::Marker *marker = new lay::Marker (view (), m_cv_index, ! show_shapes_of_instances (), show_shapes_of_instances () ? max_shapes_of_instances () : 0);
+    marker->set_vertex_shape (lay::ViewOp::Cross);
+    marker->set_vertex_size (9 /*cross vertex size*/);
+    set_edit_marker (marker);
+
     db::CellInstArray inst;
     if (get_inst (inst)) {
       marker->set (inst, m_trans);
+    } else {
+      marker->set ();
     }
+
+  } else {
+    set_edit_marker (0);
   }
 }
 
@@ -1692,14 +1943,9 @@ InstService::get_inst (db::CellInstArray &inst)
 
       //  compute the instance's transformation
       db::VCplxTrans pt = (db::CplxTrans (cv->layout ().dbu ()) * m_trans).inverted ();
-      db::ICplxTrans trans;
-      if (m_in_drag_drop) {
-        trans = db::ICplxTrans (1.0, 0.0, false, pt * m_disp - db::Point ());
-      } else {
-        trans = db::ICplxTrans (m_scale, m_angle, m_mirror, pt * m_disp - db::Point ());
-      } 
+      db::ICplxTrans trans = db::ICplxTrans (m_scale, m_angle, m_mirror, pt * m_disp - db::Point ());
 
-      if (! m_in_drag_drop && m_array && m_rows > 0 && m_columns > 0) {
+      if (m_array && m_rows > 0 && m_columns > 0) {
         db::Vector row = db::Vector (pt * db::DVector (m_row_x, m_row_y));
         db::Vector column = db::Vector (pt * db::DVector (m_column_x, m_column_y));
         inst = db::CellInstArray (db::CellInst (ci.second), trans, row, column, m_rows, m_columns);
diff --git a/src/edt/edt/edtServiceImpl.h b/src/edt/edt/edtServiceImpl.h
index 60955035b..f10c82a30 100644
--- a/src/edt/edt/edtServiceImpl.h
+++ b/src/edt/edt/edtServiceImpl.h
@@ -32,13 +32,12 @@
 namespace lay
 {
   class CellView;
+  class LayerPropertiesConstIterator;
 }
 
 namespace edt
 {
 
-class PCellParametersDialog;
-
 /**
  *  @brief Implementation of the edt::Service for generic shape editing
  */
@@ -57,15 +56,17 @@ protected:
   db::Cell &cell () const              { return *mp_cell; }
   db::Layout &layout () const          { return *mp_layout; }
 
-  void do_mouse_move_inactive (const db::DPoint &p);
+  virtual void do_mouse_move_inactive (const db::DPoint &p);
+  virtual void tap (const db::DPoint &initial);
+
+  virtual bool configure (const std::string &name, const std::string &value);
 
-  bool configure (const std::string &name, const std::string &value);
-  
 protected:
   std::pair <bool, db::DPoint> interpolate (const db::DPoint &m, const db::DPoint &o, const db::DPoint &p) const;
   void deliver_shape (const db::Polygon &poly);
   void deliver_shape (const db::Path &path);
   void deliver_shape (const db::Box &box);
+  virtual void current_layer_changed () { }
 
 private:
   db::VCplxTrans m_trans;
@@ -74,6 +75,8 @@ private:
   db::Cell *mp_cell;
   db::Layout *mp_layout;
   combine_mode_type m_combine_mode;
+
+  void update_edit_layer (const lay::LayerPropertiesConstIterator &iter);
 };
 
 /**
@@ -88,6 +91,7 @@ public:
   virtual lay::PropertiesPage *properties_page (db::Manager *manager, QWidget *parent);
   virtual void do_begin_edit (const db::DPoint &p);
   virtual void do_mouse_move (const db::DPoint &p);
+  virtual void do_mouse_move_inactive (const db::DPoint &p);
   virtual bool do_mouse_click (const db::DPoint &p);
   virtual void do_finish_edit ();
   virtual void do_cancel_edit ();
@@ -117,6 +121,7 @@ public:
   virtual lay::PropertiesPage *properties_page (db::Manager *manager, QWidget *parent);
   virtual void do_begin_edit (const db::DPoint &p);
   virtual void do_mouse_move (const db::DPoint &p);
+  virtual void do_mouse_move_inactive (const db::DPoint &p);
   virtual bool do_mouse_click (const db::DPoint &p);
   virtual void do_finish_edit ();
   virtual void do_cancel_edit ();
@@ -143,6 +148,7 @@ public:
   virtual void do_begin_edit (const db::DPoint &p);
   virtual void do_mouse_transform (const db::DPoint &p, db::DFTrans trans);
   virtual void do_mouse_move (const db::DPoint &p);
+  virtual void do_mouse_move_inactive (const db::DPoint &p);
   virtual bool do_mouse_click (const db::DPoint &p);
   virtual void do_finish_edit ();
   virtual void do_cancel_edit ();
@@ -174,6 +180,7 @@ public:
   virtual void do_begin_edit (const db::DPoint &p);
   virtual void do_mouse_move (const db::DPoint &p);
   virtual bool do_mouse_click (const db::DPoint &p);
+  virtual void do_mouse_move_inactive (const db::DPoint &p);
   virtual void do_finish_edit ();
   virtual void do_cancel_edit ();
   virtual bool do_activated ();
@@ -206,6 +213,7 @@ public:
   
   virtual lay::PropertiesPage *properties_page (db::Manager *manager, QWidget *parent);
   virtual void do_begin_edit (const db::DPoint &p);
+  virtual void do_mouse_move_inactive (const db::DPoint &p);
   virtual void do_mouse_move (const db::DPoint &p);
   virtual bool do_mouse_click (const db::DPoint &p);
   virtual void do_mouse_transform (const db::DPoint &p, db::DFTrans trans);
@@ -220,6 +228,8 @@ public:
 
 protected:
   bool configure (const std::string &name, const std::string &value);
+  void service_configuration_changed ();
+
   void config_finalize ();
 
 private:
@@ -228,14 +238,16 @@ private:
   bool m_mirror;
   db::DPoint m_disp;
   std::string m_cell_or_pcell_name, m_lib_name;
+  std::string m_cell_or_pcell_name_previous, m_lib_name_previous;
   std::map<std::string, tl::Variant> m_pcell_parameters;
+  std::map<std::pair<std::string, std::string>, std::map<std::string, tl::Variant> > m_stored_pcell_parameters;
   bool m_is_pcell;
   bool m_array;
   unsigned int m_rows, m_columns;
   double m_row_x, m_row_y, m_column_x, m_column_y;
   bool m_place_origin;
   db::Manager::transaction_id_t m_reference_transaction_id;
-  bool m_needs_update;
+  bool m_needs_update, m_parameters_changed;
   bool m_has_valid_cell;
   bool m_in_drag_drop;
   db::cell_index_type m_current_cell;
@@ -243,14 +255,13 @@ private:
   const db::PCellDeclaration *mp_pcell_decl;
   int m_cv_index;
   db::ICplxTrans m_trans;
-  std::auto_ptr<edt::PCellParametersDialog> mp_pcell_parameters_dialog;
 
   void update_marker ();
-  void apply_edits ();
   bool get_inst (db::CellInstArray &inst);
   std::pair<bool, db::cell_index_type> make_cell (const lay::CellView &cv);
   tl::Variant get_default_layer_for_pcell ();
   void sync_to_config ();
+  void switch_cell_or_pcell (bool switch_parameters);
 };
 
 }
diff --git a/src/edt/edt/edtUtils.cc b/src/edt/edt/edtUtils.cc
index d99f85ab5..a4833a0a1 100644
--- a/src/edt/edt/edtUtils.cc
+++ b/src/edt/edt/edtUtils.cc
@@ -26,12 +26,121 @@
 #include "dbLibrary.h"
 
 #include "edtUtils.h"
+#include "edtService.h"
+
 #include "layCellView.h"
 #include "layLayoutView.h"
+#include "layEditable.h"
 #include "tlException.h"
 
 namespace edt {
 
+// -------------------------------------------------------------
+
+std::string pcell_parameters_to_string (const std::map<std::string, tl::Variant> &parameters)
+{
+  std::string param;
+
+  param = "!";  //  flags PCells
+  for (std::map<std::string, tl::Variant>::const_iterator p = parameters.begin (); p != parameters.end (); ++p) {
+    param += tl::to_word_or_quoted_string (p->first);
+    param += ":";
+    param += p->second.to_parsable_string ();
+    param += ";";
+  }
+
+  return param;
+}
+
+std::map<std::string, tl::Variant> pcell_parameters_from_string (const std::string &s)
+{
+  tl::Extractor ex (s.c_str ());
+  std::map<std::string, tl::Variant> pm;
+
+  ex.test ("!");
+
+  try {
+    while (! ex.at_end ()) {
+      std::string n;
+      ex.read_word_or_quoted (n);
+      ex.test (":");
+      ex.read (pm.insert (std::make_pair (n, tl::Variant ())).first->second);
+      ex.test (";");
+    }
+  } catch (...) {
+    //  ignore errors
+  }
+
+  return pm;
+}
+
+// -------------------------------------------------------------
+//  SelectionIterator implementation
+
+SelectionIterator::SelectionIterator (lay::LayoutView *view, bool including_transient)
+  : m_transient_mode (false)
+{
+  mp_edt_services = view->get_plugins <edt::Service> ();
+
+  m_current_service = mp_edt_services.begin ();
+  if (m_current_service != mp_edt_services.end ()) {
+    m_current_object = (*m_current_service)->selection ().begin ();
+  }
+
+  next ();
+
+  if (at_end () && including_transient) {
+
+    m_transient_mode = true;
+
+    m_current_service = mp_edt_services.begin ();
+    if (m_current_service != mp_edt_services.end ()) {
+      m_current_object = (*m_current_service)->transient_selection ().begin ();
+    }
+
+    next ();
+
+  }
+}
+
+bool
+SelectionIterator::at_end () const
+{
+  return m_current_service == mp_edt_services.end ();
+}
+
+void
+SelectionIterator::inc ()
+{
+  tl_assert (! at_end ());
+  ++m_current_object;
+}
+
+void
+SelectionIterator::next ()
+{
+  if (at_end ()) {
+    return;
+  }
+
+  const edt::Service::objects *sel = m_transient_mode ? &(*m_current_service)->transient_selection () : &(*m_current_service)->selection ();
+
+  while (m_current_object == sel->end ()) {
+
+    ++m_current_service;
+
+    if (m_current_service != mp_edt_services.end ()) {
+
+      sel = m_transient_mode ? &(*m_current_service)->transient_selection () : &(*m_current_service)->selection ();
+      m_current_object = sel->begin ();
+
+    } else {
+      break;
+    }
+
+  }
+}
+
 // -------------------------------------------------------------
 //  TransformationsVariants implementation
 //  for a lay::LayoutView
diff --git a/src/edt/edt/edtUtils.h b/src/edt/edt/edtUtils.h
index db41dbd0c..460f9a12e 100644
--- a/src/edt/edt/edtUtils.h
+++ b/src/edt/edt/edtUtils.h
@@ -27,9 +27,12 @@
 #include <limits>
 #include <list>
 #include <utility>
+#include <vector>
 
 #include <QDialog>
 
+#include "layObjectInstPath.h"
+
 #include "dbInstElement.h"
 #include "dbClipboardData.h"
 #include "dbClipboard.h"
@@ -42,6 +45,18 @@ namespace lay
 
 namespace edt {
 
+class Service;
+
+/**
+ *  @brief Serializes PCell parameters to a string
+ */
+std::string pcell_parameters_to_string (const std::map<std::string, tl::Variant> &parameters);
+
+/**
+ *  @brief Deerializes PCell parameters from a string
+ */
+std::map<std::string, tl::Variant> pcell_parameters_from_string (const std::string &s);
+
 /**
  *  @brief Fetch PCell parameters from a cell and merge the guiding shapes into them
  *
@@ -79,6 +94,73 @@ private:
   std::map < std::pair<unsigned int, unsigned int>, std::vector<db::DCplxTrans> > m_per_cv_and_layer_tv;
 };
 
+/**
+ *  @brief An iterator for the selected objects of all edt services in a layout view
+ */
+class SelectionIterator
+{
+public:
+  typedef lay::ObjectInstPath value_type;
+  typedef const lay::ObjectInstPath &reference;
+  typedef const lay::ObjectInstPath *pointer;
+
+  /**
+   *  @brief Creates a new iterator iterating over all selected edt objects from the given view
+   *
+   *  If "including_transient" is true, the transient selection will be used as fallback.
+   */
+  SelectionIterator (lay::LayoutView *view, bool including_transient = true);
+
+  /**
+   *  @brief Returns a value indicating whether the transient selection is taken
+   */
+  bool is_transient () const
+  {
+    return m_transient_mode;
+  }
+
+  /**
+   *  @brief Increments the iterator
+   */
+  void operator++ ()
+  {
+    inc ();
+    next ();
+  }
+
+  /**
+   *  @brief Dereferencing
+   */
+  const lay::ObjectInstPath &operator* () const
+  {
+    tl_assert (! at_end ());
+    return *m_current_object;
+  }
+
+  /**
+   *  @brief Arrow operator
+   */
+  const lay::ObjectInstPath *operator-> () const
+  {
+    return & operator* ();
+  }
+
+  /**
+   *  @brief Returns a value indicating whether the iterator has finished
+   */
+  bool at_end () const;
+
+private:
+  void inc ();
+  void next ();
+
+private:
+  std::vector<edt::Service *> mp_edt_services;
+  std::vector<edt::Service *>::const_iterator m_current_service;
+  std::set<lay::ObjectInstPath>::const_iterator m_current_object;
+  bool m_transient_mode;
+};
+
 } // namespace edt
 
 #endif
diff --git a/src/edt/unit_tests/edtDistributeTests.cc b/src/edt/unit_tests/edtDistributeTests.cc
new file mode 100644
index 000000000..1a3288f61
--- /dev/null
+++ b/src/edt/unit_tests/edtDistributeTests.cc
@@ -0,0 +1,159 @@
+
+/*
+
+  KLayout Layout Viewer
+  Copyright (C) 2006-2020 Matthias Koefferlein
+
+  This program is free software; you can redistribute it and/or modify
+  it under the terms of the GNU General Public License as published by
+  the Free Software Foundation; either version 2 of the License, or
+  (at your option) any later version.
+
+  This program is distributed in the hope that it will be useful,
+  but WITHOUT ANY WARRANTY; without even the implied warranty of
+  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+  GNU General Public License for more details.
+
+  You should have received a copy of the GNU General Public License
+  along with this program; if not, write to the Free Software
+  Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
+
+*/
+
+#include "tlUnitTest.h"
+
+#include "edtDistribute.h"
+
+template <class Box, class Value>
+static std::string plc2string (const edt::distributed_placer<Box, Value> &plc)
+{
+  std::string s;
+  for (typename edt::distributed_placer<Box, Value>::iterator i = plc.begin (); i != plc.end (); ++i) {
+    if (! s.empty ()) {
+       s += ",";
+    }
+    s += tl::to_string (i->first);
+    s += "[";
+    s += tl::to_string (i->second);
+    s += "]";
+  }
+  return s;
+}
+
+TEST(1) 
+{
+  edt::distributed_placer<db::Box, size_t> placer;
+
+  placer.insert (db::Box (1000, 0, 1100, 200), 0);
+  placer.insert (db::Box (2000, 0, 2100, 500), 1);
+  placer.insert (db::Box (0, -100, 100, 100), 2);
+  placer.insert (db::Box (1000, 100, 1050, 250), 3);
+  placer.insert (db::Box (1050, -50, 1100, 150), 4);
+
+  edt::distributed_placer<db::Box, size_t> p;
+
+  p = placer;
+  p.distribute_h (-1, 2, 0, 100);
+
+  EXPECT_EQ (plc2string (p), "(0,-100;100,100)[2],(200,0;300,200)[0],(400,100;450,250)[3],(550,-50;600,150)[4],(700,0;800,500)[1]");
+
+  p = placer;
+  p.distribute_h (-1, -1, 0, 100);
+
+  EXPECT_EQ (plc2string (p), "(0,-100;100,100)[2],(200,-100;300,100)[0],(400,-100;450,50)[3],(550,-100;600,100)[4],(700,-100;800,400)[1]");
+
+  p = placer;
+  p.distribute_h (-1, 0, 0, 100);
+
+  EXPECT_EQ (plc2string (p), "(0,100;100,300)[2],(200,100;300,300)[0],(400,125;450,275)[3],(550,100;600,300)[4],(700,-50;800,450)[1]");
+
+  p = placer;
+  p.distribute_h (-1, 1, 0, 100);
+
+  EXPECT_EQ (plc2string (p), "(0,300;100,500)[2],(200,300;300,500)[0],(400,350;450,500)[3],(550,300;600,500)[4],(700,0;800,500)[1]");
+
+  p = placer;
+  p.distribute_h (-1, 2, 100, 0);
+
+  EXPECT_EQ (plc2string (p), "(0,-100;100,100)[2],(100,0;200,200)[0],(200,100;250,250)[3],(300,-50;350,150)[4],(400,0;500,500)[1]");
+
+  p = placer;
+  p.distribute_h (-1, 2, 0, 0);
+
+  EXPECT_EQ (plc2string (p), "(0,-100;100,100)[2],(100,0;200,200)[0],(200,100;250,250)[3],(250,-50;300,150)[4],(300,0;400,500)[1]");
+
+  p = placer;
+  p.distribute_h (1, 2, 0, 100);
+
+  EXPECT_EQ (plc2string (p), "(1300,-100;1400,100)[2],(1500,100;1550,250)[3],(1650,-50;1700,150)[4],(1800,0;1900,200)[0],(2000,0;2100,500)[1]");
+
+  p = placer;
+  p.distribute_v (-1, 2, 0, 100);
+
+  EXPECT_EQ (plc2string (p), "(0,-100;100,100)[2],(1050,200;1100,400)[4],(1000,500;1100,700)[0],(2000,800;2100,1300)[1],(1000,1400;1050,1550)[3]");
+}
+
+
+TEST(2)
+{
+  edt::distributed_placer<db::Box, size_t> placer;
+
+  placer.insert (db::Box (-5, 1, 95, 101), 0);
+  placer.insert (db::Box (1, 95, 101, 195), 1);
+  placer.insert (db::Box (110, 105, 210, 205), 2);
+  placer.insert (db::Box (101, 0, 201, 100), 3);
+
+  edt::distributed_placer<db::Box, size_t> p;
+
+  p = placer;
+  p.distribute_matrix (-1, 0, 0, -1, 0, 0);
+
+  EXPECT_EQ (plc2string (p), "(-5,0;95,100)[0],(-5,100;95,200)[1],(95,100;195,200)[2],(95,0;195,100)[3]");
+}
+
+TEST(3)
+{
+  edt::distributed_placer<db::Box, size_t> placer;
+
+  placer.insert (db::Box (0, 20, 1, 23), 0);
+  placer.insert (db::Box (3, 8, 8, 19), 1);
+  placer.insert (db::Box (6, 0, 12, 5), 2);
+  placer.insert (db::Box (13, 1, 19, 6), 3);
+  placer.insert (db::Box (10, 16, 11, 17), 4);
+
+  edt::distributed_placer<db::Box, size_t> p;
+
+  p = placer;
+  p.distribute_matrix (-1, 0, 0, -1, 0, 0);
+
+  EXPECT_EQ (plc2string (p), "(0,17;1,20)[0],(1,5;6,16)[1],(6,0;12,5)[2],(13,0;19,5)[3],(12,16;13,17)[4]");
+}
+
+TEST(4)
+{
+  edt::distributed_placer<db::Box, size_t> placer;
+
+  placer.insert (db::Box (0, 16, 1, 20), 0);
+  placer.insert (db::Box (0, 8, 5, 19), 1);
+  placer.insert (db::Box (0, 0, 12, 5), 2);
+  placer.insert (db::Box (12, 1, 19, 6), 3);
+  placer.insert (db::Box (0, 18, 1, 19), 4);
+
+  edt::distributed_placer<db::Box, size_t> p;
+
+  p = placer;
+  p.distribute_matrix (-1, 0, 0, 1, 0, 0);
+
+  EXPECT_EQ (plc2string (p), "(6,9;7,13)[0],(1,9;6,20)[1],(0,4;12,9)[2],(12,4;19,9)[3],(0,9;1,10)[4]");
+
+  p = placer;
+  p.distribute_matrix (1, 10, 0, -1, 10, 0);
+
+  EXPECT_EQ (plc2string (p), "(-38,30;-37,34)[0],(-18,10;-13,21)[1],(-8,0;4,5)[2],(12,0;19,5)[3],(-28,30;-27,31)[4]");
+
+  p = placer;
+  p.distribute_matrix (1, 0, 1, 1, 0, 1);
+
+  EXPECT_EQ (plc2string (p), "(-9,16;-8,20)[0],(-7,9;-2,20)[1],(-1,3;11,8)[2],(12,3;19,8)[3],(-11,19;-10,20)[4]");
+}
+
diff --git a/src/edt/unit_tests/unit_tests.pro b/src/edt/unit_tests/unit_tests.pro
index 630f1cd9b..14be20d9e 100644
--- a/src/edt/unit_tests/unit_tests.pro
+++ b/src/edt/unit_tests/unit_tests.pro
@@ -8,6 +8,7 @@ include($$PWD/../../lib_ut.pri)
 
 SOURCES = \
   edtBasicTests.cc \
+    edtDistributeTests.cc
 
 INCLUDEPATH += $$EDT_INC $$TL_INC $$LAYBASIC_INC $$DB_INC $$GSI_INC
 DEPENDPATH += $$EDT_INC $$TL_INC $$LAYBASIC_INC $$DB_INC $$GSI_INC
diff --git a/src/img/img/ImagePropertiesPage.ui b/src/img/img/ImagePropertiesPage.ui
index d0453605b..2ea522bdd 100644
--- a/src/img/img/ImagePropertiesPage.ui
+++ b/src/img/img/ImagePropertiesPage.ui
@@ -1058,16 +1058,6 @@ p, li { white-space: pre-wrap; }
          <property name="bottomMargin">
           <number>0</number>
          </property>
-         <item>
-          <widget class="QCheckBox" name="preview_cbx">
-           <property name="text">
-            <string>Preview (Auto apply)</string>
-           </property>
-           <property name="checked">
-            <bool>true</bool>
-           </property>
-          </widget>
-         </item>
          <item>
           <spacer>
            <property name="orientation">
@@ -1141,7 +1131,6 @@ p, li { white-space: pre-wrap; }
   <tabstop>g_sb</tabstop>
   <tabstop>b_slider</tabstop>
   <tabstop>b_sb</tabstop>
-  <tabstop>preview_cbx</tabstop>
   <tabstop>reset_pb</tabstop>
   <tabstop>contrast_sb</tabstop>
   <tabstop>gamma_sb</tabstop>
diff --git a/src/img/img/imgPropertiesPage.cc b/src/img/img/imgPropertiesPage.cc
index f53c0a100..e16d1291d 100644
--- a/src/img/img/imgPropertiesPage.cc
+++ b/src/img/img/imgPropertiesPage.cc
@@ -26,6 +26,7 @@
 #include "imgStream.h"
 #include "layLayoutView.h"
 #include "layFileDialog.h"
+#include "layQtTools.h"
 #include "tlExceptions.h"
 #include "tlFileUtils.h"
 
@@ -73,6 +74,7 @@ void
 PropertiesPage::init ()
 {
   m_no_signals = false;
+  m_in_color_mapping_signal = false;
 
   setupUi (this);
 
@@ -108,6 +110,7 @@ PropertiesPage::init ()
   connect (browse_pb, SIGNAL (clicked ()), this, SLOT (browse ()));
   connect (colors, SIGNAL (color_changed (std::pair<QColor, QColor>)), false_color_control, SLOT (set_current_color (std::pair<QColor, QColor>)));
   connect (false_color_control, SIGNAL (selection_changed (std::pair<QColor, QColor>)), colors, SLOT (set_color (std::pair<QColor, QColor>)));
+  connect (false_color_control, SIGNAL (color_mapping_changed ()), this, SLOT (color_mapping_changed ()));
 
   connect (brightness_slider, SIGNAL (valueChanged (int)), this, SLOT (brightness_slider_changed (int)));
   connect (brightness_sb, SIGNAL (valueChanged (int)), this, SLOT (brightness_spinbox_changed (int)));
@@ -122,15 +125,22 @@ PropertiesPage::init ()
   connect (b_slider, SIGNAL (valueChanged (int)), this, SLOT (blue_slider_changed (int)));
   connect (b_sb, SIGNAL (valueChanged (double)), this, SLOT (blue_spinbox_changed (double)));
 
-  connect (false_color_control, SIGNAL (color_mapping_changed ()), this, SLOT (color_mapping_changed ()));
-  connect (false_color_control, SIGNAL (selection_changed ()), this, SLOT (color_mapping_changed ()));
-  connect (from_le, SIGNAL (returnPressed ()), this, SLOT (min_max_return_pressed ()));
-  connect (to_le, SIGNAL (returnPressed ()), this, SLOT (min_max_return_pressed ()));
-  connect (value_le, SIGNAL (returnPressed ()), this, SLOT (value_return_pressed ()));
+  connect (from_le, SIGNAL (editingFinished ()), this, SLOT (min_max_value_changed ()));
+  connect (to_le, SIGNAL (editingFinished ()), this, SLOT (min_max_value_changed ()));
+  connect (value_le, SIGNAL (editingFinished ()), this, SLOT (value_changed ()));
 
+  connect (width_le, SIGNAL (editingFinished ()), this, SIGNAL (edited ()));
+  connect (height_le, SIGNAL (editingFinished ()), this, SIGNAL (edited ()));
+  connect (x_offset_le, SIGNAL (editingFinished ()), this, SIGNAL (edited ()));
+  connect (y_offset_le, SIGNAL (editingFinished ()), this, SIGNAL (edited ()));
+  connect (angle_le, SIGNAL (editingFinished ()), this, SIGNAL (edited ()));
+  connect (shear_le, SIGNAL (editingFinished ()), this, SIGNAL (edited ()));
+  connect (persp_tx_le, SIGNAL (editingFinished ()), this, SIGNAL (edited ()));
+  connect (persp_ty_le, SIGNAL (editingFinished ()), this, SIGNAL (edited ()));
+
+  connect (mirror_cbx, SIGNAL (clicked ()), this, SIGNAL (edited ()));
   connect (reset_pb, SIGNAL (clicked ()), this, SLOT (reset_pressed ()));
   connect (save_pb, SIGNAL (clicked ()), this, SLOT (save_pressed ()));
-  connect (preview_cbx, SIGNAL (clicked ()), this, SLOT (preview_checked ()));
   connect (define_landmarks_pb, SIGNAL (clicked ()), this, SLOT (define_landmarks_pressed ()));
 }
 
@@ -202,11 +212,42 @@ PropertiesPage::readonly ()
   return false;
 }
 
-void 
-PropertiesPage::min_max_return_pressed ()
+void
+PropertiesPage::get_xmin_xmax (double &xmin, double &xmax, bool &has_error_out)
 {
-BEGIN_PROTECTED
+  bool has_error = false;
 
+  try {
+    tl::from_string (tl::to_string (from_le->text ()), xmin);
+    lay::indicate_error (from_le, 0);
+  } catch (tl::Exception &ex) {
+    lay::indicate_error (from_le, &ex);
+    has_error = true;
+  }
+
+  try {
+    tl::from_string (tl::to_string (to_le->text ()), xmax);
+    lay::indicate_error (to_le, 0);
+  } catch (tl::Exception &ex) {
+    lay::indicate_error (to_le, &ex);
+    has_error = true;
+  }
+
+  if (! has_error && xmin >= xmax) {
+    tl::Exception ex (tl::to_string (QObject::tr ("Invalid data value range (min. value must be less than max. value)")));
+    lay::indicate_error (from_le, &ex);
+    lay::indicate_error (to_le, &ex);
+    has_error = true;
+  }
+
+  if (has_error) {
+    has_error_out = true;
+  }
+}
+
+void 
+PropertiesPage::min_max_value_changed ()
+{
   value_le->setText (QString ());
   value_le->setEnabled (false);
 
@@ -214,10 +255,11 @@ BEGIN_PROTECTED
   colors->set_single_mode (false);
 
   double xmin, xmax;
-  tl::from_string (tl::to_string (from_le->text ()), xmin);
-  tl::from_string (tl::to_string (to_le->text ()), xmax);
-  if (xmin >= xmax) {
-    throw tl::Exception (tl::to_string (QObject::tr ("Invalid data value range (min. value must be less than max. value)")));
+  bool has_error = false;
+  get_xmin_xmax (xmin, xmax, has_error);
+
+  if (has_error) {
+    return;
   }
 
   if (false_color_control->has_selection () && false_color_control->selected_node () > 0 && false_color_control->selected_node () < int (false_color_control->nodes ().size ()) - 1) {
@@ -236,9 +278,7 @@ BEGIN_PROTECTED
 
   recompute_histogram ();
 
-  preview ();
-
-END_PROTECTED
+  emit edited ();
 }
 
 void
@@ -246,22 +286,20 @@ PropertiesPage::color_mapping_changed ()
 {
   if (! m_no_signals) {
 
+    bool has_error = false;
+
     value_le->setText (QString ());
     value_le->setEnabled (false);
 
     colors->setEnabled (false_color_control->has_selection ());
     colors->set_single_mode (false);
 
-    try {
+    if (false_color_control->has_selection () && false_color_control->selected_node () > 0 && false_color_control->selected_node () < int (false_color_control->nodes ().size ()) - 1) {
 
-      if (false_color_control->has_selection () && false_color_control->selected_node () > 0 && false_color_control->selected_node () < int (false_color_control->nodes ().size ()) - 1) {
+      double xmin, xmax;
+      get_xmin_xmax (xmin, xmax, has_error);
 
-        double xmin, xmax;
-        tl::from_string (tl::to_string (from_le->text ()), xmin);
-        tl::from_string (tl::to_string (to_le->text ()), xmax);
-        if (xmin >= xmax) {
-          throw tl::Exception ("");
-        }
+      if (! has_error) {
 
         double x = false_color_control->nodes () [false_color_control->selected_node ()].first;
         double xx = x * (xmax - xmin) + xmin;
@@ -269,46 +307,57 @@ PropertiesPage::color_mapping_changed ()
         value_le->setText (tl::to_qstring (tl::sprintf ("%.4g", xx)));
         value_le->setEnabled (true);
 
-      } else if (false_color_control->has_selection ()) {
-
-        colors->set_single_mode (true);
-
       }
 
-    } catch (...) { }
+    } else if (false_color_control->has_selection ()) {
 
-    preview ();
+      colors->set_single_mode (true);
+
+    }
+
+    if (! has_error) {
+      m_in_color_mapping_signal = true;
+      emit edited ();
+      m_in_color_mapping_signal = false;
+    }
 
   }
 }
 
 void
-PropertiesPage::value_return_pressed ()
+PropertiesPage::value_changed ()
 {
-BEGIN_PROTECTED
+  double xx = 0;
+  bool has_error = false;
 
   double xmin, xmax;
-  tl::from_string (tl::to_string (from_le->text ()), xmin);
-  tl::from_string (tl::to_string (to_le->text ()), xmax);
-  if (xmin >= xmax) {
-    throw tl::Exception (tl::to_string (QObject::tr ("Invalid data value range (min. value must be less than max. value)")));
-  }
+  get_xmin_xmax (xmin, xmax, has_error);
 
   double x = 0.0;
-  tl::from_string (tl::to_string (value_le->text ()), x);
-
-  double xx = (x - xmin) / (xmax - xmin);
-  if (xx < 0 || xx > 1.0) {
-    throw tl::Exception (tl::to_string (QObject::tr ("The position entered (%g) must be between the minimum (%g) and maximum (%g) value")), x, xmin, xmax);
+  try {
+    tl::from_string (tl::to_string (value_le->text ()), x);
+    lay::indicate_error (value_le, 0);
+  } catch (tl::Exception &ex) {
+    lay::indicate_error (value_le, &ex);
+    has_error = true;
   }
 
-  m_no_signals = true;
-  false_color_control->set_current_position (xx);
-  m_no_signals = false;
+  xx = (x - xmin) / (xmax - xmin);
+  if (! has_error && (xx < 0 || xx > 1.0)) {
+    tl::Exception ex (tl::to_string (QObject::tr ("The position entered (%g) must be between the minimum (%g) and maximum (%g) value")), x, xmin, xmax);
+    lay::indicate_error (value_le, &ex);
+    has_error = true;
+  }
 
-  preview ();
+  if (! has_error) {
 
-END_PROTECTED
+    m_no_signals = true;
+    false_color_control->set_current_position (xx);
+    m_no_signals = false;
+
+    emit edited ();
+
+  }
 }
 
 inline double 
@@ -320,6 +369,10 @@ round_to_zero (double x)
 void 
 PropertiesPage::update ()
 {
+  if (m_in_color_mapping_signal) {
+    return;
+  }
+
   m_no_signals = true;
 
   if (mp_service) {
@@ -498,7 +551,7 @@ PropertiesPage::brightness_slider_changed (int value)
 
   m_no_signals = true;
   brightness_sb->setValue (value);
-  preview ();
+  emit edited ();
   m_no_signals = false;
 }
 
@@ -511,7 +564,7 @@ PropertiesPage::brightness_spinbox_changed (int value)
 
   m_no_signals = true;
   brightness_slider->setValue (value);
-  preview ();
+  emit edited ();
   m_no_signals = false;
 }
 
@@ -524,7 +577,7 @@ PropertiesPage::contrast_slider_changed (int value)
 
   m_no_signals = true;
   contrast_sb->setValue (value);
-  preview ();
+  emit edited ();
   m_no_signals = false;
 }
 
@@ -537,7 +590,7 @@ PropertiesPage::contrast_spinbox_changed (int value)
 
   m_no_signals = true;
   contrast_slider->setValue (value);
-  preview ();
+  emit edited ();
   m_no_signals = false;
 }
 
@@ -556,7 +609,7 @@ PropertiesPage::gamma_spinbox_changed (double value)
     gamma_slider->setValue (50 + int (0.5 + (value - 1.0) / (max_gamma - 1.0) * 50.0));
   }
 
-  preview ();
+  emit edited ();
 
   m_no_signals = false;
 }
@@ -578,7 +631,7 @@ PropertiesPage::gamma_slider_changed (int value)
   }
 
   gamma_sb->setValue (gamma);
-  preview ();
+  emit edited ();
 
   m_no_signals = false;
 }
@@ -595,7 +648,7 @@ PropertiesPage::red_slider_changed (int value)
   double gain = value * 0.02;
 
   r_sb->setValue (gain);
-  preview ();
+  emit edited ();
 
   m_no_signals = false;
 }
@@ -610,7 +663,7 @@ PropertiesPage::red_spinbox_changed (double value)
   m_no_signals = true;
 
   r_slider->setValue (int (0.5 + value * 50.0));
-  preview ();
+  emit edited ();
 
   m_no_signals = false;
 }
@@ -627,7 +680,7 @@ PropertiesPage::green_slider_changed (int value)
   double gain = value * 0.02;
 
   g_sb->setValue (gain);
-  preview ();
+  emit edited ();
 
   m_no_signals = false;
 }
@@ -642,7 +695,7 @@ PropertiesPage::green_spinbox_changed (double value)
   m_no_signals = true;
 
   g_slider->setValue (int (0.5 + value * 50.0));
-  preview ();
+  emit edited ();
 
   m_no_signals = false;
 }
@@ -659,7 +712,7 @@ PropertiesPage::blue_slider_changed (int value)
   double gain = value * 0.02;
 
   b_sb->setValue (gain);
-  preview ();
+  emit edited ();
 
   m_no_signals = false;
 }
@@ -674,9 +727,9 @@ PropertiesPage::blue_spinbox_changed (double value)
   m_no_signals = true;
 
   b_slider->setValue (int (0.5 + value * 50.0));
-  preview ();
+  emit edited ();
 
-  m_no_signals = false;
+  m_no_signals = false;  
 }
 
 void  
@@ -686,6 +739,7 @@ PropertiesPage::black_to_white ()
   nodes.push_back (std::make_pair (0.0, std::make_pair (QColor (0, 0, 0), QColor (0, 0, 0))));
   nodes.push_back (std::make_pair (1.0, std::make_pair (QColor (255, 255, 255), QColor (255, 255, 255))));
   false_color_control->set_nodes (nodes);
+  emit edited ();
 }
 
 void  
@@ -695,6 +749,7 @@ PropertiesPage::white_to_black ()
   nodes.push_back (std::make_pair (0.0, std::make_pair (QColor (255, 255, 255), QColor (255, 255, 255))));
   nodes.push_back (std::make_pair (1.0, std::make_pair (QColor (0, 0, 0), QColor (0, 0, 0))));
   false_color_control->set_nodes (nodes);
+  emit edited ();
 }
 
 void  
@@ -704,7 +759,7 @@ PropertiesPage::red_to_blue ()
   nodes.push_back (std::make_pair (0.0, std::make_pair (QColor (255, 0, 0), QColor (255, 0, 0))));
   nodes.push_back (std::make_pair (1.0, std::make_pair (QColor (0, 0, 255), QColor (0, 0, 255))));
   false_color_control->set_nodes (nodes);
-
+  emit edited ();
 }
 
 void  
@@ -714,6 +769,7 @@ PropertiesPage::blue_to_red ()
   nodes.push_back (std::make_pair (0.0, std::make_pair (QColor (0, 0, 255), QColor (0, 0, 255))));
   nodes.push_back (std::make_pair (1.0, std::make_pair (QColor (255, 0, 0), QColor (255, 0, 0))));
   false_color_control->set_nodes (nodes);
+  emit edited ();
 }
 
 void  
@@ -725,11 +781,14 @@ PropertiesPage::reverse_color_order ()
     std::swap (nodes [i].second.first, nodes [nodes.size () - 1 - i].second.second);
   }
   false_color_control->set_nodes (nodes);
+  emit edited ();
 }
 
 void 
 PropertiesPage::apply ()
 {
+  bool has_error = false;
+
   db::Matrix3d matrix = mp_direct_image->matrix ();
 
   //  The observer distance for perspective distortion is the average of the images width and height.
@@ -741,45 +800,89 @@ PropertiesPage::apply ()
   double w = matrix.mag_x (), h = matrix.mag_y (), x = matrix.disp ().x (), y = matrix.disp ().y (), 
          a = matrix.angle (), sa = matrix.shear_angle (), tx = matrix.perspective_tilt_x (z), ty = matrix.perspective_tilt_y (z);
 
-  bool mirror;
-
-  if (width_le->text () != tl::to_qstring (tl::micron_to_string (matrix.mag_x ()))) {
+  try {
     tl::from_string (tl::to_string (width_le->text ()), w);
+    if (w <= 0.0 || h <= 0.0) {
+      throw tl::Exception (tl::to_string (QObject::tr ("Pixel width or height must be positive, non-null values")));
+    }
+    lay::indicate_error (width_le, 0);
+  } catch (tl::Exception &ex) {
+    lay::indicate_error (width_le, &ex);
+    has_error = true;
   }
-  if (height_le->text () != tl::to_qstring (tl::micron_to_string (matrix.mag_y ()))) {
+
+  try {
     tl::from_string (tl::to_string (height_le->text ()), h);
+    lay::indicate_error (height_le, 0);
+  } catch (tl::Exception &ex) {
+    lay::indicate_error (height_le, &ex);
+    has_error = true;
   }
-  if (x_offset_le->text () != tl::to_qstring (tl::micron_to_string (round_to_zero (matrix.disp ().x ())))) {
+
+  try {
     tl::from_string (tl::to_string (x_offset_le->text ()), x);
+    lay::indicate_error (x_offset_le, 0);
+  } catch (tl::Exception &ex) {
+    lay::indicate_error (x_offset_le, &ex);
+    has_error = true;
   }
-  if (y_offset_le->text () != tl::to_qstring (tl::micron_to_string (round_to_zero (matrix.disp ().y ())))) {
+
+  try {
     tl::from_string (tl::to_string (y_offset_le->text ()), y);
+    lay::indicate_error (y_offset_le, 0);
+  } catch (tl::Exception &ex) {
+    lay::indicate_error (y_offset_le, &ex);
+    has_error = true;
   }
-  if (angle_le->text () != tl::to_qstring (tl::to_string (round_to_zero (matrix.angle ())))) {
+
+  try {
     tl::from_string (tl::to_string (angle_le->text ()), a);
+    lay::indicate_error (angle_le, 0);
+  } catch (tl::Exception &ex) {
+    lay::indicate_error (angle_le, &ex);
+    has_error = true;
   }
-  if (shear_le->text () != tl::to_qstring (tl::to_string (round_to_zero (matrix.shear_angle ())))) {
+
+  try {
     tl::from_string (tl::to_string (shear_le->text ()), sa);
+    if (sa <= -45 || sa >= 45) {
+      throw tl::Exception (tl::to_string (QObject::tr ("The shear angle must be larger than -45 and less than 45 degree")));
+    }
+    lay::indicate_error (shear_le, 0);
+  } catch (tl::Exception &ex) {
+    lay::indicate_error (shear_le, &ex);
+    has_error = true;
   }
-  if (persp_tx_le->text () != tl::to_qstring (tl::to_string (round_to_zero (matrix.perspective_tilt_x (z))))) {
+
+  try {
     tl::from_string (tl::to_string (persp_tx_le->text ()), tx);
+    if (tx <= -90 || tx >= 90) {
+      throw tl::Exception (tl::to_string (QObject::tr ("The perspective tilt angles must be larger than -90 and less than 90 degree")));
+    }
+    lay::indicate_error (persp_tx_le, 0);
+  } catch (tl::Exception &ex) {
+    lay::indicate_error (persp_tx_le, &ex);
+    has_error = true;
   }
-  if (persp_ty_le->text () != tl::to_qstring (tl::to_string (round_to_zero (matrix.perspective_tilt_y (z))))) {
+
+  try {
     tl::from_string (tl::to_string (persp_ty_le->text ()), ty);
+    if (ty <= -90 || ty >= 90) {
+      throw tl::Exception (tl::to_string (QObject::tr ("The perspective tilt angles must be larger than -90 and less than 90 degree")));
+    }
+    lay::indicate_error (persp_ty_le, 0);
+  } catch (tl::Exception &ex) {
+    lay::indicate_error (persp_ty_le, &ex);
+    has_error = true;
   }
 
-  mirror = mirror_cbx->isChecked ();
+  bool mirror = mirror_cbx->isChecked ();
 
-  if (w <= 0.0 || h <= 0.0) {
-    throw tl::Exception (tl::to_string (QObject::tr ("Pixel width or height must be positive, non-null values")));
-  }
+  double xmin, xmax;
+  get_xmin_xmax (xmin, xmax, has_error);
 
-  if (sa <= -45 || sa >= 45) {
-    throw tl::Exception (tl::to_string (QObject::tr ("The shear angle must be larger than -45 and less than 45 degree")));
-  }
-
-  if (tx <= -90 || tx >= 90 || ty <= -90 || ty >= 90) {
-    throw tl::Exception (tl::to_string (QObject::tr ("The perspective tilt angles must be larger than -90 and less than 90 degree")));
+  if (has_error) {
+    throw tl::Exception (tl::to_string (tr ("At least one value is invalid - see highlighted entry fields")));
   }
 
   //  Compute the new observer distance
@@ -790,13 +893,6 @@ PropertiesPage::apply ()
   matrix = db::Matrix3d::disp (db::DVector (x, y)) * db::Matrix3d::perspective (tx, ty, z) * db::Matrix3d::rotation (a) * db::Matrix3d::shear (sa) * db::Matrix3d::mag (w, h) * db::Matrix3d::mirror (mirror);
   mp_direct_image->set_matrix (matrix);
 
-  double xmin, xmax;
-  tl::from_string (tl::to_string (from_le->text ()), xmin);
-  tl::from_string (tl::to_string (to_le->text ()), xmax);
-  if (xmin >= xmax) {
-    throw tl::Exception (tl::to_string (QObject::tr ("Invalid data value range (min. value must be less than max. value)")));
-  }
-
   mp_direct_image->set_min_value (xmin);
   mp_direct_image->set_max_value (xmax);
 
@@ -891,30 +987,7 @@ PropertiesPage::reset_pressed ()
 
   m_no_signals = false;
 
-  preview ();
-}
-
-void
-PropertiesPage::preview_checked ()
-{
-  preview ();
-}
-
-void
-PropertiesPage::preview ()
-{
-  if (preview_cbx->isChecked ()) {
-
-    BEGIN_PROTECTED_CLEANUP
-
-    apply (); // this is a HACK, because it changes the current object
-
-    END_PROTECTED_CLEANUP
-    {
-      preview_cbx->setChecked (false);
-    }
-
-  }
+  emit edited ();
 }
 
 void
@@ -922,7 +995,9 @@ PropertiesPage::define_landmarks_pressed ()
 {
   if (mp_direct_image) {
     img::LandmarksDialog dialog (this, *mp_direct_image);
-    dialog.exec ();
+    if (dialog.exec ()) {
+      emit edited ();
+    }
   }
 }
 
diff --git a/src/img/img/imgPropertiesPage.h b/src/img/img/imgPropertiesPage.h
index 1de6a3f88..8a45bd186 100644
--- a/src/img/img/imgPropertiesPage.h
+++ b/src/img/img/imgPropertiesPage.h
@@ -64,7 +64,7 @@ public:
 
 private slots:
   void browse ();
-  void value_return_pressed ();
+  void value_changed ();
   void color_mapping_changed ();
   void brightness_slider_changed (int value);
   void brightness_spinbox_changed (int value);
@@ -83,8 +83,7 @@ private slots:
   void red_to_blue ();
   void blue_to_red ();
   void reverse_color_order ();
-  void min_max_return_pressed ();
-  void preview_checked ();
+  void min_max_value_changed ();
   void reset_pressed ();
   void save_pressed ();
   void define_landmarks_pressed ();
@@ -95,11 +94,12 @@ private:
   img::Service *mp_service;
   img::Object *mp_direct_image;
   bool m_no_signals;
+  bool m_in_color_mapping_signal;
 
   void recompute_histogram ();
   void invalidate ();
   void init ();
-  void preview ();
+  void get_xmin_xmax (double &xmin, double &xmax, bool &has_error_out);
 };
 
 }
diff --git a/src/klayout.pri b/src/klayout.pri
index d9d1fdc41..245b3f12d 100644
--- a/src/klayout.pri
+++ b/src/klayout.pri
@@ -160,7 +160,7 @@ equals(HAVE_QT, "0") {
 } else {
 
   DEFINES += HAVE_QT
-  QT += core network xml sql
+  QT += core network xml sql widgets
 
   equals(HAVE_QT5, "1") {
     QT += designer printsupport
diff --git a/src/lay/lay/HelpDialog.ui b/src/lay/lay/HelpDialog.ui
new file mode 100644
index 000000000..19c3f1e66
--- /dev/null
+++ b/src/lay/lay/HelpDialog.ui
@@ -0,0 +1,75 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<ui version="4.0">
+ <class>HelpDialog</class>
+ <widget class="QDialog" name="HelpDialog">
+  <property name="geometry">
+   <rect>
+    <x>0</x>
+    <y>0</y>
+    <width>900</width>
+    <height>500</height>
+   </rect>
+  </property>
+  <property name="windowTitle">
+   <string>Assistant</string>
+  </property>
+  <layout class="QVBoxLayout" name="verticalLayout">
+   <property name="leftMargin">
+    <number>9</number>
+   </property>
+   <property name="topMargin">
+    <number>4</number>
+   </property>
+   <property name="rightMargin">
+    <number>9</number>
+   </property>
+   <property name="bottomMargin">
+    <number>9</number>
+   </property>
+   <item>
+    <widget class="lay::BrowserPanel" name="browser_panel" native="true">
+     <property name="sizePolicy">
+      <sizepolicy hsizetype="Preferred" vsizetype="Preferred">
+       <horstretch>0</horstretch>
+       <verstretch>1</verstretch>
+      </sizepolicy>
+     </property>
+    </widget>
+   </item>
+   <item>
+    <widget class="QDialogButtonBox" name="button_frame">
+     <property name="standardButtons">
+      <set>QDialogButtonBox::Close</set>
+     </property>
+    </widget>
+   </item>
+  </layout>
+ </widget>
+ <customwidgets>
+  <customwidget>
+   <class>lay::BrowserPanel</class>
+   <extends>QWidget</extends>
+   <header>layBrowserPanel.h</header>
+   <container>1</container>
+  </customwidget>
+ </customwidgets>
+ <resources/>
+ <connections>
+  <connection>
+   <sender>button_frame</sender>
+   <signal>rejected()</signal>
+   <receiver>HelpDialog</receiver>
+   <slot>accept()</slot>
+   <hints>
+    <hint type="sourcelabel">
+     <x>436</x>
+     <y>487</y>
+    </hint>
+    <hint type="destinationlabel">
+     <x>309</x>
+     <y>498</y>
+    </hint>
+   </hints>
+  </connection>
+ </connections>
+</ui>
diff --git a/src/lay/lay/doc/about/custom_queries.xml b/src/lay/lay/doc/about/custom_queries.xml
index 2f4f5acb0..02c70381b 100644
--- a/src/lay/lay/doc/about/custom_queries.xml
+++ b/src/lay/lay/doc/about/custom_queries.xml
@@ -104,7 +104,7 @@ cells T*
 </pre>
 
   <p>
-  A cell expression can already be used by it's own. The report of such a query will simply contain the cells
+  A cell expression can already be used by its own. The report of such a query will simply contain the cells
   selected by that expression. If combined with an action, such expressions already provide useful manipulation
   functionality.
   </p>
@@ -243,7 +243,7 @@ cells TOP..A
   is used in (including top cells and all child contexts). Used after a cell, it will return the cell 
   plus all child cells in each possible context. Used before a cell it will deliver all contexts that cell
   is used in every top cells. 
-  The following query will deliver "TOP" plus all it's direct and indirect children:
+  The following query will deliver "TOP" plus all its direct and indirect children:
   </p>
 
   <pre>
@@ -398,7 +398,7 @@ with shapes on layer 6 from instances of TOP.. do initial_cell.shapes(&lt;10/0&g
 </pre>
 
   <p>
-  That expression reads all shapes of cell "TOP" and it's children, inserts them into a new layer 10, datatype 0 and
+  That expression reads all shapes of cell "TOP" and its children, inserts them into a new layer 10, datatype 0 and
   transforms the shape after it has been inserted. This expression makes use of the variables "initial_cell" (a Cell object
   representing the root cell of the cell query), "shape" (a pointer to the currently selected shape and "path_trans"
   (a Trans object representing the transformation of the current shape into the root cell of the query). 
diff --git a/src/lay/lay/doc/about/drc_ref_global.xml b/src/lay/lay/doc/about/drc_ref_global.xml
index 76ed7823d..6f80c8b5a 100644
--- a/src/lay/lay/doc/about/drc_ref_global.xml
+++ b/src/lay/lay/doc/about/drc_ref_global.xml
@@ -164,7 +164,7 @@ end
 </pre>
 </p><p>
 (Technically, the cheat code block is a Ruby Proc and cannot create variables
-outside it's scope. Hence the results of this code block have to be passed
+outside its scope. Hence the results of this code block have to be passed
 through the "cheat" method).
 </p><p>
 To apply cheats for device extraction, use the following scheme:
diff --git a/src/lay/lay/doc/about/drc_ref_netter.xml b/src/lay/lay/doc/about/drc_ref_netter.xml
index 6d4a91380..a0b2b14b3 100644
--- a/src/lay/lay/doc/about/drc_ref_netter.xml
+++ b/src/lay/lay/doc/about/drc_ref_netter.xml
@@ -302,7 +302,7 @@ Predefined device extractors are:
 <li><a href="/about/drc_ref_global.xml#capacitor_with_bulk">global#capacitor_with_bulk</a> - A capacitor with a separate bulk terminal </li>
 </ul>
 </p><p>
-Each device class (e.g. n-MOS/p-MOS or high Vt/low Vt) needs it's own instance
+Each device class (e.g. n-MOS/p-MOS or high Vt/low Vt) needs its own instance
 of device extractor. The device extractor beside the algorithm and specific 
 extraction settings defines the name of the device to be built.
 </p><p>
diff --git a/src/lay/lay/doc/about/drc_ref_source.xml b/src/lay/lay/doc/about/drc_ref_source.xml
index d30545115..7b29857d1 100644
--- a/src/lay/lay/doc/about/drc_ref_source.xml
+++ b/src/lay/lay/doc/about/drc_ref_source.xml
@@ -282,19 +282,34 @@ To disable the TOP cell but enabled a hypothetical cell B below the top cell, us
 code:
 </p><p>
 <pre>
-layout_with_selection = layout.select("-TOP", "+B")
-l1 = layout_with_selection.input(1, 0)
+layout_with_selection = source.select("-TOP", "+B")
+l1 = source.input(1, 0)
 ...
 </pre>
 </p><p>
 Please note that the sample above will deliver the children of "B" because there is 
-nothing said about how to proceed with cells other than "TOP" or "B".
-The following code will just select "B" without it's children, because in the 
+nothing said about how to proceed with cells other than "TOP" or "B". Conceptually,
+the instantiation path of a cell will be matched against the different filters in the
+order they are given.
+A matching negative expression will disable the cell, a matching positive expression
+will enable the cell. Hence, every cell that has a "B" in the instantiation path 
+is enabled.
+</p><p>
+The following code will just select "B" without its children, because in the 
 first "-*" selection, all cells including the children of "B" are disabled:
 </p><p>
 <pre>
-layout_with_selection = layout.select("-*", "+B")
-l1 = layout_with_selection.input(1, 0)
+layout_with_selection = source.select("-*", "+B")
+l1 = source.input(1, 0)
+...
+</pre>
+</p><p>
+The short form "-" will disable the top cell. This code is identical to the first example
+and will start with a disabled top cell regardless of its name:
+</p><p>
+<pre>
+layout_with_selection = source.select("-", "+B")
+l1 = source.input(1, 0)
 ...
 </pre>
 </p>
diff --git a/src/lay/lay/doc/about/layer_mapping.xml b/src/lay/lay/doc/about/layer_mapping.xml
index b9209e016..81d6205db 100644
--- a/src/lay/lay/doc/about/layer_mapping.xml
+++ b/src/lay/lay/doc/about/layer_mapping.xml
@@ -130,7 +130,7 @@
   <p>
   If the match expression includes a numerical range or wildcards
   for the layer or datatype number, by default all these layers
-  will be combined into a single one, where it's layer or datatype number is derived
+  will be combined into a single one, where its layer or datatype number is derived
   from the least permitted number.
   </p>
 
diff --git a/src/lay/lay/doc/about/technology_manager.xml b/src/lay/lay/doc/about/technology_manager.xml
index 1cc3fa189..a9c508fa9 100644
--- a/src/lay/lay/doc/about/technology_manager.xml
+++ b/src/lay/lay/doc/about/technology_manager.xml
@@ -37,7 +37,7 @@
       edited. Instead, a library installed in the system comes with a technology 
       association itself.</li>
     <li>File format options: technology specific file reader or writer options can be
-      given. When a layout is saved, it will use the writer options from it's technology.
+      given. When a layout is saved, it will use the writer options from its technology.
       When loading a layout, the reader options from the active technology will be used.</li>
   </ul>
 
diff --git a/src/lay/lay/doc/manual/copypaste_cell.xml b/src/lay/lay/doc/manual/copypaste_cell.xml
index 519e7ebf5..97d59e700 100644
--- a/src/lay/lay/doc/manual/copypaste_cell.xml
+++ b/src/lay/lay/doc/manual/copypaste_cell.xml
@@ -28,7 +28,7 @@
       cells with the same name will be used as child cells.
     </li>
     <li>
-      <b>Deep copy</b>: In deep copy mode, the cell plus it's child cells are copied. All cells will be carried
+      <b>Deep copy</b>: In deep copy mode, the cell plus its child cells are copied. All cells will be carried
       along and when pasting the cell, copies of all children will be created as well.
     </li>
   </ul>    
diff --git a/src/lay/lay/doc/manual/create_instance.xml b/src/lay/lay/doc/manual/create_instance.xml
index 07f6c6897..11b6922ab 100644
--- a/src/lay/lay/doc/manual/create_instance.xml
+++ b/src/lay/lay/doc/manual/create_instance.xml
@@ -57,7 +57,7 @@
   <p>
   KLayout offers a unique feature for the PCell implementation: a PCell can employ "guiding shapes".
   "Guiding shapes" are shapes that do not appear as layout themselves but are used by the PCell
-  to derive it's geometry from. For example the "rounded path" PCell of the "Basic" library 
+  to derive its geometry from. For example the "rounded path" PCell of the "Basic" library 
   uses a path as a guiding shape. This path is manipulated to obtain the final shape. 
   </p>
 
diff --git a/src/lay/lay/doc/manual/del_cell.xml b/src/lay/lay/doc/manual/del_cell.xml
index e03b36750..7662c96a7 100644
--- a/src/lay/lay/doc/manual/del_cell.xml
+++ b/src/lay/lay/doc/manual/del_cell.xml
@@ -13,13 +13,13 @@
   </p>
 
   <ul>
-    <li><b>Shallow delete:</b> Just the cell (it's shapes and instances) are deleted, not
+    <li><b>Shallow delete:</b> Just the cell (its shapes and instances) are deleted, not
       any cells referenced by this cell. Since cells might no longer be referenced after
       that, they may appear as new top cells in the layout.</li>
-    <li><b>Deep delete:</b> The cell and all it's subcells are deleted, unless the subcells are
+    <li><b>Deep delete:</b> The cell and all its subcells are deleted, unless the subcells are
       referenced otherwise (by cells that are not deleted).
       In this delete mode a complete hierarchy of cells can be removed without side effects.</li>
-    <li><b>Complete delete:</b> The cell and all it's subcells are deleted, even if other cells
+    <li><b>Complete delete:</b> The cell and all its subcells are deleted, even if other cells
       would reference these subcells.</li>
   </ul>
 
diff --git a/src/lay/lay/doc/manual/flatten.xml b/src/lay/lay/doc/manual/flatten.xml
index 9238089e8..d01579b59 100644
--- a/src/lay/lay/doc/manual/flatten.xml
+++ b/src/lay/lay/doc/manual/flatten.xml
@@ -8,7 +8,7 @@
   <keyword name="Editing"/>
 
   <p>
-  The "flatten cell" operation flattens a cell into all of it's parents.
+  The "flatten cell" operation flattens a cell into all of its parents.
   This basically removes a cell by promoting her shapes and instances up in the hierarchy.
   </p>
 
@@ -16,7 +16,7 @@
   Cell flattening can be applied to single instances or cells as a whole.
   When applied to an instance, the individual instance is resolved into shapes. The 
   instantiated cell will still exist afterwards. When applied to a cell, the cell 
-  will disappear and replaced by it's contents in all places it is used.
+  will disappear and replaced by its contents in all places it is used.
   </p>
 
   <p>
diff --git a/src/lay/lay/doc/manual/hier_ops.xml b/src/lay/lay/doc/manual/hier_ops.xml
index 7f010a337..326492d5f 100644
--- a/src/lay/lay/doc/manual/hier_ops.xml
+++ b/src/lay/lay/doc/manual/hier_ops.xml
@@ -23,7 +23,7 @@
       are brought up to the current cell's level and removed from the original cell.<br/>
       A non-destructive way of moving a shape up in the hierarchy is to copy and paste the shape. This does an 
       explicit flattening of the shapes selected when inserting them.<br/>
-      <b>Hint:</b> the current implementation removes the selected object from it's original cell. Since it only creates
+      <b>Hint:</b> the current implementation removes the selected object from its original cell. Since it only creates
       new copies for the selected instances, the object ist lost for all other instances of the cell. This may create undesired
       side effects and it is likely that this behaviour will change in future implementations.
       </li>
diff --git a/src/lay/lay/doc/manual/lvs_tweaks.xml b/src/lay/lay/doc/manual/lvs_tweaks.xml
index 2e631f677..12e4b0bf5 100644
--- a/src/lay/lay/doc/manual/lvs_tweaks.xml
+++ b/src/lay/lay/doc/manual/lvs_tweaks.xml
@@ -101,7 +101,7 @@
   act as a wrapper to something else. In layouts, devices are often implemented as PCells and 
   appear as specific cells for no other reason than being implemented in a subcell. The same 
   might happen for schematic subcircuits which wrap a device. "Flattening" means that a circuit
-  is removed and it's contents are integrated into the calling circuits.
+  is removed and its contents are integrated into the calling circuits.
   </p>
 
   <p>
diff --git a/src/lay/lay/doc/manual/main_window.xml b/src/lay/lay/doc/manual/main_window.xml
index d4a7f6ae6..c98c2ef45 100644
--- a/src/lay/lay/doc/manual/main_window.xml
+++ b/src/lay/lay/doc/manual/main_window.xml
@@ -10,7 +10,7 @@
   The main window is divided into three parts: the left area is the hierarchy browser and navigator, the 
   center part of the canvas and the right part is the layer list with the layer toolbox.
   The individual components can be rearranged, so the arrangement described is just the default
-  arrangement. You can move a component to a new place by dragging it with it's title bar to 
+  arrangement. You can move a component to a new place by dragging it with its title bar to 
   some other place or detach it from the main window to form a floating separate window.
   </p>
 
diff --git a/src/lay/lay/doc/manual/move_sel.xml b/src/lay/lay/doc/manual/move_sel.xml
index 4799fd5d7..72403a30c 100644
--- a/src/lay/lay/doc/manual/move_sel.xml
+++ b/src/lay/lay/doc/manual/move_sel.xml
@@ -40,7 +40,7 @@
   In the same way, "Move To" allows one to reposition the selection to a certain point. The point which
   is positioned can be chosen relative to the bounding box of the selection. If first example,
   the lower-left corner of the selection is picked as the reference point and a certain position
-  is given in the dialog, the selection is moved such that the lower left position of it's
+  is given in the dialog, the selection is moved such that the lower left position of its
   bounding box will match the given coordinate.
   </p>
 
diff --git a/src/lay/lay/doc/manual/panels.xml b/src/lay/lay/doc/manual/panels.xml
index 1abaa5183..265baee06 100644
--- a/src/lay/lay/doc/manual/panels.xml
+++ b/src/lay/lay/doc/manual/panels.xml
@@ -30,7 +30,7 @@
   <p>
   Choose "Pull In Other Layout" to combine other layouts already loaded into the
   current panel. Basically, KLayout allows viewsing a layout in multiple panels, either
-  on it's own in different configurations or together with other layouts. "Pull In Other Layout" 
+  on its own in different configurations or together with other layouts. "Pull In Other Layout" 
   allows configuration of a panel to show another layout which has been loaded into another panel.
   In that sense it's the reverse of closing one layout from a panel showing multiple layouts.
   </p>
diff --git a/src/lay/lay/doc/manual/ruler_properties.xml b/src/lay/lay/doc/manual/ruler_properties.xml
index bfcababf0..d889bd883 100644
--- a/src/lay/lay/doc/manual/ruler_properties.xml
+++ b/src/lay/lay/doc/manual/ruler_properties.xml
@@ -20,7 +20,7 @@
       The Alignment of the labels can be specified too: whether the appear left or right-aligned
       or centered.
     </li>
-    <li><b>Style:</b> the style determines how the ruler or it's components are drawn. This can be
+    <li><b>Style:</b> the style determines how the ruler or its components are drawn. This can be
       "ruler-like" (with ticks), arrow style, a plain line or with cross markers at the end.
     </li>
     <li><b>Outline:</b> the outline determines how the two points forming the ruler are connected
@@ -31,7 +31,7 @@
     </li>
     <li><b>Angle constraint:</b> the orientation of the ruler can be restricted in several ways, i.e. 
       just being horizontal. By default, the ruler uses the global setting. It can however be configured 
-      to provide it's own constraint.
+      to provide its own constraint.
     </li>
     <li><b>Object snapping:</b> each ruler can be configure to snap to the closest object edge or vertex.
       By default, the rulers use the global setting. It may be disabled however for each ruler.
diff --git a/src/lay/lay/doc/programming/application_api.xml b/src/lay/lay/doc/programming/application_api.xml
index 1fb7914fe..5baee3f8d 100644
--- a/src/lay/lay/doc/programming/application_api.xml
+++ b/src/lay/lay/doc/programming/application_api.xml
@@ -206,7 +206,7 @@ Application::instance.main_window.views</pre>
     to a large degree, so different colors can be used for example. Markers are objects of class
     Marker (<class_doc href="Marker"/>).
     </li>
-    <li><b>Local configuration</b>: be default, the layout view pulls it's configuration from the global
+    <li><b>Local configuration</b>: be default, the layout view pulls its configuration from the global
     configuration database. It is possible however to override certain configuration parameters for a 
     particular view. This allows for example to set the background color for a particular view without
     affecting the other views.
@@ -703,7 +703,7 @@ layout_view.insert_layer(lp, props)
   Width is a "weak" property. That means that for computing the effective width, child nodes 
   can override the settings inherited from the parent nodes. A width of 0 is considered "not set" and does not
   override parent defined widths. Other properties like visibility are "strong", i.e. 
-  the parent can override the properties set for it's children. Another form of combination is "additive" where
+  the parent can override the properties set for its children. Another form of combination is "additive" where
   the effective property value is the "sum" (or in general combination) of all local properties from parent
   to child.
   </p>
diff --git a/src/lay/lay/doc/programming/database_api.xml b/src/lay/lay/doc/programming/database_api.xml
index 3607af938..07fe4b06a 100644
--- a/src/lay/lay/doc/programming/database_api.xml
+++ b/src/lay/lay/doc/programming/database_api.xml
@@ -161,7 +161,7 @@ layout.write("my_layout.gds")</pre>
   </p>
 
   <p>
-  A layout can provide and import PCells. PCells are cells that provide it's geometry through program code
+  A layout can provide and import PCells. PCells are cells that provide its geometry through program code
   (for example written in Ruby) and provide parameters which can be adjusted to change the appearance of the 
   cell. For each PCell a "declaration" must be provided which basically contains the code for the 
   PCell and some information about the parameters provided by the PCell. PCells are stored in the layout
@@ -473,6 +473,13 @@ shape.set_property(1, "NewValue")</pre>
   and "delete_property" also are provided for cells and cell instances (<class_doc href="Cell"/> and <class_doc href="Instance"/>).
   </p>
 
+  <p>
+  <b>Note:</b> The GDS format does not have string names for properties. As a result GDS only supports numeric property keys.
+  OASIS, on the other hand, can handle string and numeric property "names". When saving layouts in GDS format, KLayout tries
+  to convert the properties' names into numbers if possible (i.e. if it sees that the string is a number). If it can't, then
+  the property is not saved. When the layout is read by KLayout upon opening, it gets converted to integer.
+  </p>
+
   <h2>The LayerInfo class</h2>
 
   <keyword name="LayerInfo"/>
@@ -813,7 +820,7 @@ end</pre>
 
   <keyword name="CellInstArray"/>
   <p>
-  Despite it's name, a <class_doc href="CellInstArray"/> object holds a cell reference which is
+  Despite its name, a <class_doc href="CellInstArray"/> object holds a cell reference which is
   not only an array, but also a single instances. The object represents a raw instance, in contrast to the 
   Instance object which is basically a pointer to an instance inside the database. CellInstArray objects as raw instances can be created, 
   copied, modified and stored in the usual containers, but once they are stored inside the Cell object, they can
@@ -1060,7 +1067,7 @@ end</pre>
   The <class_doc href="Shape"/> object provides a unified view to a geometrical primitive inside
   a Shapes container. It also plays an important role for addressing geometrical primitives 
   inside a Shapes container. A Shape object has general methods and specific methods that apply 
-  depending on it's identity.
+  depending on its identity.
   </p>
 
   <h3>General methods</h3>
diff --git a/src/lay/lay/doc/programming/events.xml b/src/lay/lay/doc/programming/events.xml
index ee9b4e657..827102a7c 100644
--- a/src/lay/lay/doc/programming/events.xml
+++ b/src/lay/lay/doc/programming/events.xml
@@ -108,7 +108,7 @@ end</pre>
   <p>
   Events are the callback variant which is the easiest one to use. Using an event it is possible
   to directly attach a block of code to a callback. An event has a specific signature, i.e. 
-  the parameters it provides. The block can obtain this parameters by listing them in it's argument list.
+  the parameters it provides. The block can obtain this parameters by listing them in its argument list.
   </p>
 
   <p>
diff --git a/src/lay/lay/doc/programming/geometry_api.xml b/src/lay/lay/doc/programming/geometry_api.xml
index e0628293c..cff528b57 100644
--- a/src/lay/lay/doc/programming/geometry_api.xml
+++ b/src/lay/lay/doc/programming/geometry_api.xml
@@ -36,7 +36,7 @@
   The <class_doc href="Point"/> object represents an integer coordinate in the 2-dimensional layout space,
   expressed in database units. 
   That object provides the x and y coordinates through the <class_doc href="Point#x"/> and <class_doc href="Point#y"/> attributes. Points can be added, 
-  subtracted, the euclidian distance and it's square can be computed using the <class_doc href="Point#distance"/> and <class_doc href="Point#sq_distance"/>
+  subtracted, the euclidian distance and its square can be computed using the <class_doc href="Point#distance"/> and <class_doc href="Point#sq_distance"/>
   methods. The <b>*</b> operator used with a factor as the second operand will scale both the x and y coordinates.
   </p>
 
@@ -113,7 +113,7 @@
     <li><b>Box + Point</b>: computes the box that encloses the box and the point given
     as the second operand. It basically enlarges the first box so it includes the second point as well.
     </li>
-    <li><b>contains?(Point)</b>: returns true, if the point is inside the box or on it's edges.
+    <li><b>contains?(Point)</b>: returns true, if the point is inside the box or on its edges.
     </li>
     <li><b>enlarge(Point)</b>: will enlarge the box by the x and y coordinates of the Point. Basically the x value
     of the point is subtracted from the left side and added to the right. The same way, the y coordinate is added
@@ -272,7 +272,7 @@ box = RBA::Box::new(dbox)
 
   <p>
   A <class_doc href="Path"/> object represents a line with a certain width. The figure above depicts the basic properties
-  of a path. The basic geometry of a path is defined by it's spine - a sequence of points that the path follows.
+  of a path. The basic geometry of a path is defined by its spine - a sequence of points that the path follows.
   By default, a path has rectangular end caps with variable length. The end caps can be round, in which case the extension 
   should be half the path width to avoid paths which are not compatible with the GDS2 format. Round-ended paths return
   true on <class_doc href="Path#is_round?"/>. An example for such a path is depicted in the following figure:
@@ -641,7 +641,7 @@ ly.top_cell.shapes(ly.layer(100, 0)).insert(r11 &amp; r21)
     <class_doc href="EdgePairs"/> edge pair collections, not regions. Each edge pair marks a
     violation of the given check.
   </p>
-  <p><class_doc href="Region#extents"/> replaces each polygon with it's bounding box.</p>
+  <p><class_doc href="Region#extents"/> replaces each polygon with its bounding box.</p>
   <p><class_doc href="Region#grid_check"/> performs an on-grid check returning edge pairs for off-grid markers.</p>
   <p><class_doc href="Region#holes"/> identifies holes and delivers a new region with the holes as filled polygons.</p>
   <p><class_doc href="Region#hulls"/> identifies holes and delivers a new region without the holes.</p>
diff --git a/src/lay/lay/doc/programming/qt_binding.xml b/src/lay/lay/doc/programming/qt_binding.xml
index ae227cfa3..7d5c22b3a 100644
--- a/src/lay/lay/doc/programming/qt_binding.xml
+++ b/src/lay/lay/doc/programming/qt_binding.xml
@@ -165,7 +165,7 @@ end</pre>
   </p>
 
   <p>
-  When a Qt object is created in Ruby space with a parent, it's 
+  When a Qt object is created in Ruby space with a parent, its 
   ownership is passed to the parent. It is safe however to keep a reference to that object, because
   KLayout's Ruby binding employs a special Ruby class internally (a proxy) which keeps track of the lifetime
   of the Qt object. If the parent is destroyed, the Qt object is destroyed as well. The internal Qt object will
diff --git a/src/lay/lay/doc/programming/ruby_binding.xml b/src/lay/lay/doc/programming/ruby_binding.xml
index 7449de54a..6ff93b20c 100644
--- a/src/lay/lay/doc/programming/ruby_binding.xml
+++ b/src/lay/lay/doc/programming/ruby_binding.xml
@@ -119,7 +119,7 @@ cell.shapes(layer).insert(box)</pre>
   An exception to the lifetime control rule given above are Qt objects: a common pattern is to create Qt objects 
   and add them to a container (i.e. widgets to a dialog). This implies a lifetime control transfer from
   Ruby to C++. RBA handles that case by explicitly transferring control when a QObject or one of the
-  derived objects is created with a parent reference in Ruby code. Qt implements it's own mechanism of controlling
+  derived objects is created with a parent reference in Ruby code. Qt implements its own mechanism of controlling
   the lifetime which includes monitoring of the lifetime of child objects. This feature makes transferring the
   control feasible for these kind of objects. For some Qt methods which are know to transfer the ownership 
   of an object, the ownership is transferred explicitly.
diff --git a/src/lay/lay/doc/programming/ruby_pcells.xml b/src/lay/lay/doc/programming/ruby_pcells.xml
index caabcf7ac..d068d3ef5 100644
--- a/src/lay/lay/doc/programming/ruby_pcells.xml
+++ b/src/lay/lay/doc/programming/ruby_pcells.xml
@@ -310,7 +310,7 @@ end</pre>
   is used for the cell tree and cell box labels. To avoid confusion, it should start with the name of the
   PCell. The bracket notation is not mandatory, but it's always a good idea to follow some common style.
   The information delivered by this method should be short but contain enough information so that a 
-  PCell variant can be distinguished from it's sibling. 
+  PCell variant can be distinguished from its sibling. 
   </p>
 
   <p>
diff --git a/src/lay/lay/images/back.png b/src/lay/lay/images/back.png
index bfd1a9f3a..f106b46a5 100644
Binary files a/src/lay/lay/images/back.png and b/src/lay/lay/images/back.png differ
diff --git a/src/lay/lay/images/back_16.png b/src/lay/lay/images/back_16.png
index b7d8e2918..b5c926f50 100644
Binary files a/src/lay/lay/images/back_16.png and b/src/lay/lay/images/back_16.png differ
diff --git a/src/lay/lay/images/bookmark.png b/src/lay/lay/images/bookmark.png
new file mode 100644
index 000000000..c315058ce
Binary files /dev/null and b/src/lay/lay/images/bookmark.png differ
diff --git a/src/lay/lay/images/bookmark_16.png b/src/lay/lay/images/bookmark_16.png
new file mode 100644
index 000000000..59767c43a
Binary files /dev/null and b/src/lay/lay/images/bookmark_16.png differ
diff --git a/src/lay/lay/images/fit_back.png b/src/lay/lay/images/fit_back.png
new file mode 100644
index 000000000..cbfbbad30
Binary files /dev/null and b/src/lay/lay/images/fit_back.png differ
diff --git a/src/lay/lay/images/fit_bottom.png b/src/lay/lay/images/fit_bottom.png
new file mode 100644
index 000000000..7308be3a2
Binary files /dev/null and b/src/lay/lay/images/fit_bottom.png differ
diff --git a/src/lay/lay/images/fit_front.png b/src/lay/lay/images/fit_front.png
new file mode 100644
index 000000000..5034b975b
Binary files /dev/null and b/src/lay/lay/images/fit_front.png differ
diff --git a/src/lay/lay/images/fit_left.png b/src/lay/lay/images/fit_left.png
new file mode 100644
index 000000000..36dc09f5c
Binary files /dev/null and b/src/lay/lay/images/fit_left.png differ
diff --git a/src/lay/lay/images/fit_right.png b/src/lay/lay/images/fit_right.png
new file mode 100644
index 000000000..d422ad54c
Binary files /dev/null and b/src/lay/lay/images/fit_right.png differ
diff --git a/src/lay/lay/images/fit_top.png b/src/lay/lay/images/fit_top.png
new file mode 100644
index 000000000..843fd32d6
Binary files /dev/null and b/src/lay/lay/images/fit_top.png differ
diff --git a/src/lay/lay/images/forward.png b/src/lay/lay/images/forward.png
index 19b9eb896..6dbc76455 100644
Binary files a/src/lay/lay/images/forward.png and b/src/lay/lay/images/forward.png differ
diff --git a/src/lay/lay/images/forward_16.png b/src/lay/lay/images/forward_16.png
index 23cbccb8a..fa9e7a261 100644
Binary files a/src/lay/lay/images/forward_16.png and b/src/lay/lay/images/forward_16.png differ
diff --git a/src/lay/lay/images/home.png b/src/lay/lay/images/home.png
index eb50c31ea..7cee0be19 100644
Binary files a/src/lay/lay/images/home.png and b/src/lay/lay/images/home.png differ
diff --git a/src/lay/lay/images/next_topic.png b/src/lay/lay/images/next_topic.png
index 63e9f391f..2ba1acba3 100644
Binary files a/src/lay/lay/images/next_topic.png and b/src/lay/lay/images/next_topic.png differ
diff --git a/src/lay/lay/images/prev_topic.png b/src/lay/lay/images/prev_topic.png
index 46a833c67..141bc71f8 100644
Binary files a/src/lay/lay/images/prev_topic.png and b/src/lay/lay/images/prev_topic.png differ
diff --git a/src/lay/lay/lay.pro b/src/lay/lay/lay.pro
index cfb7e9c75..f2ba59502 100644
--- a/src/lay/lay/lay.pro
+++ b/src/lay/lay/lay.pro
@@ -9,9 +9,11 @@ DEFINES += MAKE_LAY_LIBRARY
 HEADERS = \
     layApplication.h \
     layClipDialog.h \
+    layControlWidgetStack.h \
     layCrashMessage.h \
     layFillDialog.h \
     layGSIHelpProvider.h \
+    layHelpAboutDialog.h \
     layHelpDialog.h \
     layHelpProvider.h \
     layHelpSource.h \
@@ -25,6 +27,7 @@ HEADERS = \
     layMainWindow.h \
     layNavigator.h \
     layProgress.h \
+    layProgressDialog.h \
     layProgressWidget.h \
     layResourceHelpProvider.h \
     layRuntimeErrorForm.h \
@@ -35,6 +38,7 @@ HEADERS = \
     laySettingsForm.h \
     layTechSetupDialog.h \
     layTextProgress.h \
+    layTextProgressDelegate.h \
     layVersion.h \
     layCommon.h \
     layConfig.h \
@@ -57,7 +61,8 @@ HEADERS = \
     layMacroEditorSetupPage.h \
     layPasswordDialog.h \
     layForceLink.h \
-    layInit.h
+    layInit.h \
+    layViewWidgetStack.h
 
 FORMS = \
     ClipDialog.ui \
@@ -66,6 +71,7 @@ FORMS = \
     DeleteModeDialog.ui \
     FillDialog.ui \
     HelpAboutDialog.ui \
+    HelpDialog.ui \
     LogViewerDialog.ui \
     MacroEditorDialog.ui \
     MacroPropertiesDialog.ui \
@@ -112,9 +118,11 @@ SOURCES = \
     gsiDeclLayMainWindow.cc \
     layApplication.cc \
     layClipDialog.cc \
+    layControlWidgetStack.cc \
     layCrashMessage.cc \
     layFillDialog.cc \
     layGSIHelpProvider.cc \
+    layHelpAboutDialog.cc \
     layHelpDialog.cc \
     layHelpProvider.cc \
     layHelpSource.cc \
@@ -128,6 +136,7 @@ SOURCES = \
     layMainWindow.cc \
     layNavigator.cc \
     layProgress.cc \
+    layProgressDialog.cc \
     layProgressWidget.cc \
     layResourceHelpProvider.cc \
     layRuntimeErrorForm.cc \
@@ -139,6 +148,7 @@ SOURCES = \
     laySettingsForm.cc \
     layTechSetupDialog.cc \
     layTextProgress.cc \
+    layTextProgressDelegate.cc \
     layVersion.cc \
     layMacroController.cc \
     layTechnologyController.cc \
@@ -159,7 +169,8 @@ SOURCES = \
     layMacroEditorSetupPage.cc \
     layPasswordDialog.cc \
     layForceLink.cc \
-    layInit.cc
+    layInit.cc \
+    layViewWidgetStack.cc
 
 RESOURCES = layBuildInMacros.qrc \
     layHelpResources.qrc \
@@ -179,6 +190,10 @@ win32 {
   LIBS += -lpsapi -ldbghelp
 }
 
+*bsd* {
+  LIBS += -lexecinfo
+}
+
 # Note: this accounts for UI-generated headers placed into the output folders in
 # shadow builds:
 INCLUDEPATH += $$DESTDIR/laybasic/laybasic
diff --git a/src/lay/lay/layConfig.h b/src/lay/lay/layConfig.h
index 9c5e9d58a..541d9f4ef 100644
--- a/src/lay/lay/layConfig.h
+++ b/src/lay/lay/layConfig.h
@@ -40,6 +40,9 @@ static const std::string cfg_synchronized_views ("synchronized-views");
 static const std::string cfg_edit_mode ("edit-mode");
 static const std::string cfg_custom_macro_paths ("custom-macro-paths");
 static const std::string cfg_mru ("mru");
+static const std::string cfg_mru_layer_properties ("mru-layer-properties");
+static const std::string cfg_mru_sessions ("mru-sessions");
+static const std::string cfg_mru_bookmarks ("mru-bookmarks");
 static const std::string cfg_technologies ("technology-data");
 static const std::string cfg_key_bindings ("key-bindings");
 static const std::string cfg_menu_items_hidden ("menu-items-hidden");
@@ -57,6 +60,7 @@ static const std::string cfg_layout_file_watcher_enabled ("layout-file-watcher-e
 static const std::string cfg_window_geometry ("window-geometry");
 static const std::string cfg_micron_digits ("digits-micron");
 static const std::string cfg_dbu_digits ("digits-dbu");
+static const std::string cfg_assistant_bookmarks ("assistant-bookmarks");
 
 }
 
diff --git a/src/lay/lay/layControlWidgetStack.cc b/src/lay/lay/layControlWidgetStack.cc
new file mode 100644
index 000000000..a4806323e
--- /dev/null
+++ b/src/lay/lay/layControlWidgetStack.cc
@@ -0,0 +1,141 @@
+
+/*
+
+  KLayout Layout Viewer
+  Copyright (C) 2006-2020 Matthias Koefferlein
+
+  This program is free software; you can redistribute it and/or modify
+  it under the terms of the GNU General Public License as published by
+  the Free Software Foundation; either version 2 of the License, or
+  (at your option) any later version.
+
+  This program is distributed in the hope that it will be useful,
+  but WITHOUT ANY WARRANTY; without even the implied warranty of
+  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+  GNU General Public License for more details.
+
+  You should have received a copy of the GNU General Public License
+  along with this program; if not, write to the Free Software
+  Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
+
+*/
+
+#include "layControlWidgetStack.h"
+
+#include <QLabel>
+
+namespace lay
+{
+
+ControlWidgetStack::ControlWidgetStack(QWidget *parent, const char *name)
+  : QFrame (parent), mp_current_widget (0)
+{
+  setObjectName (QString::fromUtf8 (name));
+
+  //  Background ist a simple label without a text currently
+  mp_bglabel = new QLabel (this);
+  mp_bglabel->setAutoFillBackground (true);
+  mp_bglabel->setAlignment (Qt::AlignVCenter | Qt::AlignHCenter);
+  mp_bglabel->show ();
+}
+
+void ControlWidgetStack::focusInEvent(QFocusEvent *)
+{
+  for (size_t i = 0; i < m_widgets.size (); ++i) {
+    if (m_widgets [i]->isVisible ()) {
+      m_widgets [i]->setFocus ();
+      break;
+    }
+  }
+}
+
+void ControlWidgetStack::add_widget(QWidget *w)
+{
+  m_widgets.push_back (w);
+  w->setParent (this);
+  resize_children ();
+  raise_widget (m_widgets.size () - 1);
+
+  int mw = 0;
+  for (size_t i = 0; i < m_widgets.size (); ++i) {
+    mw = std::max (m_widgets [i]->sizeHint ().width (), mw);
+    mw = std::max (m_widgets [i]->minimumWidth (), mw);
+  }
+
+  if (mw > minimumWidth ()) {
+    setMinimumWidth (mw);
+    resize (minimumWidth (), height ());
+  }
+}
+
+QSize ControlWidgetStack::sizeHint() const
+{
+  int w = 0;
+  for (size_t i = 0; i < m_widgets.size (); ++i) {
+    w = std::max (m_widgets [i]->sizeHint ().width (), w);
+  }
+  return QSize (w, 0);
+}
+
+void ControlWidgetStack::remove_widget(size_t index)
+{
+  if (index < m_widgets.size ()) {
+    if (mp_current_widget == m_widgets [index]) {
+      mp_current_widget = 0;
+    }
+    m_widgets.erase (m_widgets.begin () + index);
+  }
+  if (m_widgets.size () == 0) {
+    mp_bglabel->show ();
+  }
+}
+
+void ControlWidgetStack::raise_widget(size_t index)
+{
+  mp_current_widget = 0;
+  bool any_visible = false;
+  for (size_t i = 0; i < m_widgets.size (); ++i) {
+    if (m_widgets [i]) {
+      if (i == index) {
+        m_widgets [i]->show ();
+        mp_current_widget = m_widgets [i];
+        any_visible = true;
+      } else {
+        m_widgets [i]->hide ();
+      }
+    }
+  }
+
+  if (! any_visible) {
+    mp_bglabel->show ();
+  } else {
+    mp_bglabel->hide ();
+  }
+}
+
+QWidget *ControlWidgetStack::widget(size_t index)
+{
+  if (index < m_widgets.size ()) {
+    return m_widgets [index];
+  } else {
+    return 0;
+  }
+}
+
+QWidget *ControlWidgetStack::background_widget()
+{
+  return mp_bglabel;
+}
+
+void ControlWidgetStack::resize_children()
+{
+  //  set the geometry of all children
+  for (std::vector <QWidget *>::iterator child = m_widgets.begin (); child != m_widgets.end (); ++child) {
+    if (*child) {
+      (*child)->setGeometry (0, 0, width (), height ());
+    }
+  }
+  mp_bglabel->setGeometry (0, 0, width (), height ());
+}
+
+}
diff --git a/src/lay/lay/layControlWidgetStack.h b/src/lay/lay/layControlWidgetStack.h
new file mode 100644
index 000000000..29b436a68
--- /dev/null
+++ b/src/lay/lay/layControlWidgetStack.h
@@ -0,0 +1,77 @@
+
+/*
+
+  KLayout Layout Viewer
+  Copyright (C) 2006-2020 Matthias Koefferlein
+
+  This program is free software; you can redistribute it and/or modify
+  it under the terms of the GNU General Public License as published by
+  the Free Software Foundation; either version 2 of the License, or
+  (at your option) any later version.
+
+  This program is distributed in the hope that it will be useful,
+  but WITHOUT ANY WARRANTY; without even the implied warranty of
+  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+  GNU General Public License for more details.
+
+  You should have received a copy of the GNU General Public License
+  along with this program; if not, write to the Free Software
+  Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
+
+*/
+
+
+#ifndef HDR_layControlWidgetStack
+#define HDR_layControlWidgetStack
+
+#include "layCommon.h"
+
+#include <QFrame>
+
+class QLabel;
+
+namespace lay
+{
+
+class ControlWidgetStack
+  : public QFrame
+{
+public:
+  ControlWidgetStack (QWidget *parent = 0, const char *name = 0);
+
+  void focusInEvent (QFocusEvent *);
+
+  QSize sizeHint () const;
+
+  void add_widget (QWidget *w);
+  void remove_widget (size_t index);
+  void raise_widget (size_t index);
+  QWidget *widget (size_t index);
+  QWidget *background_widget ();
+
+  QWidget *currentWidget () const
+  {
+    return mp_current_widget;
+  }
+
+  size_t count () const
+  {
+    return m_widgets.size ();
+  }
+
+protected:
+  virtual void resizeEvent (QResizeEvent *)
+  {
+    resize_children ();
+  }
+
+  void resize_children ();
+
+  std::vector <QWidget *> m_widgets;
+  QWidget *mp_current_widget;
+  QLabel *mp_bglabel;
+};
+
+}
+
+#endif
diff --git a/src/lay/lay/layGSIHelpProvider.cc b/src/lay/lay/layGSIHelpProvider.cc
index 171b3fc6a..b44c91a4a 100644
--- a/src/lay/lay/layGSIHelpProvider.cc
+++ b/src/lay/lay/layGSIHelpProvider.cc
@@ -318,6 +318,55 @@ real_class (const gsi::ClassBase *cls)
   return cls->declaration () ? cls->declaration () : cls;
 }
 
+namespace {
+
+class RecursiveClassIterator
+{
+public:
+  typedef const gsi::ClassBase &reference;
+  typedef const gsi::ClassBase *pointer;
+
+  RecursiveClassIterator ()
+  {
+    if (gsi::ClassBase::begin_classes () != gsi::ClassBase::end_classes ()) {
+      m_cls_iter_stack.push_back (std::make_pair (gsi::ClassBase::begin_classes (), gsi::ClassBase::end_classes ()));
+    }
+  }
+
+  bool at_end () const
+  {
+    return m_cls_iter_stack.empty ();
+  }
+
+  RecursiveClassIterator &operator++ ()
+  {
+    if (operator* ().begin_child_classes () != operator* ().end_child_classes ()) {
+      m_cls_iter_stack.push_back (std::make_pair (operator* ().begin_child_classes (), operator* ().end_child_classes ()));
+    } else {
+      while (! m_cls_iter_stack.empty () && ++m_cls_iter_stack.back ().first == m_cls_iter_stack.back ().second) {
+        m_cls_iter_stack.pop_back ();
+      }
+    }
+
+    return *this;
+  }
+
+  const gsi::ClassBase &operator* () const
+  {
+    return *m_cls_iter_stack.back ().first;
+  }
+
+  const gsi::ClassBase *operator-> () const
+  {
+    return m_cls_iter_stack.back ().first.operator-> ();
+  }
+
+private:
+  std::list<std::pair<gsi::ClassBase::class_iterator, gsi::ClassBase::class_iterator> > m_cls_iter_stack;
+};
+
+}
+
 static std::string
 replace_references (const std::string &t, const gsi::ClassBase *cls_base)
 {
@@ -341,7 +390,7 @@ replace_references (const std::string &t, const gsi::ClassBase *cls_base)
     r += std::string (t, q, p - q);
 
     size_t pp = ++p;
-    while (p < t.size () && (t[p] == '_' || isalnum (t [p]))) {
+    while (p < t.size () && (t[p] == '_' || t[p] == ':' || isalnum (t [p]))) {
       ++p;
     }
     if (p < t.size () && (t[p] == '?' || t [p] == '=')) {
@@ -369,8 +418,8 @@ replace_references (const std::string &t, const gsi::ClassBase *cls_base)
       found = true;
     }
 
-    for (gsi::ClassBase::class_iterator c = gsi::ClassBase::begin_classes (); c != gsi::ClassBase::end_classes () && !found; ++c) {
-      if (c->name () == id) {
+    for (RecursiveClassIterator c; ! c.at_end (); ++c) {
+      if (c->qname () == id) {
         r += "<a href=\"";
         if (mid.empty ()) {
           r += escape_xml (class_doc_url (id));
diff --git a/src/lay/lay/layHelpAboutDialog.cc b/src/lay/lay/layHelpAboutDialog.cc
new file mode 100644
index 000000000..6430d43a1
--- /dev/null
+++ b/src/lay/lay/layHelpAboutDialog.cc
@@ -0,0 +1,140 @@
+
+/*
+
+  KLayout Layout Viewer
+  Copyright (C) 2006-2020 Matthias Koefferlein
+
+  This program is free software; you can redistribute it and/or modify
+  it under the terms of the GNU General Public License as published by
+  the Free Software Foundation; either version 2 of the License, or
+  (at your option) any later version.
+
+  This program is distributed in the hope that it will be useful,
+  but WITHOUT ANY WARRANTY; without even the implied warranty of
+  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+  GNU General Public License for more details.
+
+  You should have received a copy of the GNU General Public License
+  along with this program; if not, write to the Free Software
+  Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
+
+*/
+
+#include "layHelpAboutDialog.h"
+#include "layApplication.h"
+#include "layVersion.h"
+#include "layHelpSource.h" // because of escape_xml
+#include "layInit.h"
+#include "dbInit.h"
+#include "gsiInterpreter.h"
+
+#include "ui_HelpAboutDialog.h"
+
+#include <list>
+
+namespace lay
+{
+
+// ------------------------------------------------------------
+//  Implementation of the "help about" dialog
+
+HelpAboutDialog::HelpAboutDialog (QWidget *parent)
+  : QDialog (parent)
+{
+  mp_ui = new Ui::HelpAboutDialog ();
+  mp_ui->setupUi (this);
+
+  std::vector<std::string> build_options;
+  if (lay::ApplicationBase::instance ()->ruby_interpreter ().available ()) {
+    build_options.push_back (tl::to_string (tr ("Ruby interpreter ")) + lay::ApplicationBase::instance ()->ruby_interpreter ().version ());
+  }
+  if (lay::ApplicationBase::instance ()->python_interpreter ().available ()) {
+    build_options.push_back (tl::to_string (tr ("Python interpreter ")) + lay::ApplicationBase::instance ()->python_interpreter ().version ());
+  }
+#if defined(HAVE_QTBINDINGS)
+  build_options.push_back (tl::to_string (tr ("Qt bindings for scripts")));
+#endif
+#if defined(HAVE_64BIT_COORD)
+  build_options.push_back (tl::to_string (tr ("Wide coordinates (64 bit)")));
+#endif
+
+  std::string s;
+
+  s = "<html><body>";
+
+  s += "<h1>";
+  s += escape_xml (std::string (lay::Version::name ()) + " " + lay::Version::version ());
+  s += "</h1>";
+
+  std::vector<std::string> about_paras = tl::split (lay::Version::about_text (), "\n\n");
+  for (std::vector<std::string>::const_iterator p = about_paras.begin (); p != about_paras.end (); ++p) {
+    s += std::string ("<p>") + escape_xml (*p) + "</p>";
+  }
+
+  if (! build_options.empty ()) {
+    s += "<p>";
+    s += "<h4>";
+    s += escape_xml (tl::to_string (QObject::tr ("Build options:")));
+    s += "</h4><ul>";
+    for (std::vector<std::string>::const_iterator bo = build_options.begin (); bo != build_options.end (); ++bo) {
+      s += "<li>";
+      s += escape_xml (*bo);
+      s += "</li>";
+    }
+    s += "</ul>";
+  }
+
+  if (! lay::plugins ().empty () || ! db::plugins ().empty ()) {
+
+    s += "<p>";
+    s += "<h4>";
+    s += escape_xml (tl::to_string (QObject::tr ("Binary extensions:")));
+    s += "</h4><ul>";
+
+    for (std::list<lay::PluginDescriptor>::const_iterator pd = lay::plugins ().begin (); pd != lay::plugins ().end (); ++pd) {
+      s += "<li>";
+      if (! pd->description.empty ()) {
+        s += escape_xml (pd->description);
+      } else {
+        s += escape_xml (pd->path);
+      }
+      if (! pd->version.empty ()) {
+        s += " (" + escape_xml (pd->version) + ")";
+      }
+      s += "</li>";
+    }
+
+    for (std::list<db::PluginDescriptor>::const_iterator pd = db::plugins ().begin (); pd != db::plugins ().end (); ++pd) {
+      s += "<li>";
+      if (! pd->description.empty ()) {
+        s += escape_xml (pd->description);
+      } else {
+        s += escape_xml (pd->path);
+      }
+      if (! pd->version.empty ()) {
+        s += " (" + escape_xml (pd->version) + ")";
+      }
+      s += "</li>";
+    }
+
+    s += "</ul>";
+
+  }
+
+  s += "</body></html>";
+
+  std::string t = tl::to_string (QObject::tr ("About ")) + lay::Version::name ();
+
+  setWindowTitle (tl::to_qstring (t));
+
+  mp_ui->main->setWordWrap (true);
+  mp_ui->main->setText (tl::to_qstring (s));
+}
+
+HelpAboutDialog::~HelpAboutDialog ()
+{
+  delete mp_ui;
+  mp_ui = 0;
+}
+
+}
diff --git a/src/lay/lay/layHelpAboutDialog.h b/src/lay/lay/layHelpAboutDialog.h
new file mode 100644
index 000000000..fc98fe98e
--- /dev/null
+++ b/src/lay/lay/layHelpAboutDialog.h
@@ -0,0 +1,55 @@
+
+/*
+
+  KLayout Layout Viewer
+  Copyright (C) 2006-2020 Matthias Koefferlein
+
+  This program is free software; you can redistribute it and/or modify
+  it under the terms of the GNU General Public License as published by
+  the Free Software Foundation; either version 2 of the License, or
+  (at your option) any later version.
+
+  This program is distributed in the hope that it will be useful,
+  but WITHOUT ANY WARRANTY; without even the implied warranty of
+  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+  GNU General Public License for more details.
+
+  You should have received a copy of the GNU General Public License
+  along with this program; if not, write to the Free Software
+  Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
+
+*/
+
+
+#ifndef HDR_layHelpAboutDialog
+#define HDR_layHelpAboutDialog
+
+#include "layCommon.h"
+
+#include <QDialog>
+
+namespace Ui {
+  class HelpAboutDialog;
+}
+
+namespace lay
+{
+
+/**
+ *  @brief A dialog for showing the "help about" dialog
+ */
+class LAY_PUBLIC HelpAboutDialog
+  : public QDialog
+{
+public:
+  HelpAboutDialog (QWidget *parent);
+  ~HelpAboutDialog ();
+
+private:
+  Ui::HelpAboutDialog *mp_ui;
+};
+
+}
+
+#endif
+
diff --git a/src/lay/lay/layHelpDialog.cc b/src/lay/lay/layHelpDialog.cc
index 36fd04864..47f603666 100644
--- a/src/lay/lay/layHelpDialog.cc
+++ b/src/lay/lay/layHelpDialog.cc
@@ -24,7 +24,10 @@
 #include "layHelpDialog.h"
 #include "layHelpSource.h"
 #include "layBrowserPanel.h"
+#include "layDispatcher.h"
+#include "layConfig.h"
 #include "tlStaticObjects.h"
+#include "ui_HelpDialog.h"
 
 #include "tlString.h"
 
@@ -42,35 +45,17 @@ HelpDialog::HelpDialog (QWidget *parent, bool modal)
   : QDialog (modal ? parent : 0 /*show as separate window*/, modal ? Qt::WindowFlags (0) : Qt::Window /*enabled minimize button*/),
     m_initialized (false)
 {
+  mp_ui = new Ui::HelpDialog ();
+  mp_ui->setupUi (this);
+
   setModal (modal);
 
-  QVBoxLayout *help_layout = new QVBoxLayout (this);
-  setLayout (help_layout);
-  setWindowTitle (QObject::tr ("Assistant"));
-  mp_browser_panel = new lay::BrowserPanel (this);
-  help_layout->addWidget (mp_browser_panel);
-
-  QSizePolicy sp = mp_browser_panel->sizePolicy ();
-  sp.setVerticalStretch (1);
-  mp_browser_panel->setSizePolicy (sp);
-
-  if (modal) {
-    QFrame *button_frame = new QFrame (this);
-    help_layout->addWidget (button_frame);
-    QHBoxLayout *button_layout = new QHBoxLayout (button_frame);
-    button_layout->setMargin (0);
-    QPushButton *close_button = new QPushButton (button_frame);
-    button_layout->addStretch (1);
-    button_layout->addWidget (close_button);
-    close_button->setText (QObject::tr ("Close"));
-    close_button->setDefault (false);
-    close_button->setAutoDefault (false);
-    connect (close_button, SIGNAL (clicked ()), this, SLOT (accept ()));
-  }
+  mp_ui->button_frame->setVisible (modal);
+  mp_ui->browser_panel->set_dispatcher (lay::Dispatcher::instance (), cfg_assistant_bookmarks);
 
   m_def_title = windowTitle ();
-  connect (mp_browser_panel, SIGNAL (title_changed (const QString &)), this, SLOT (title_changed (const QString &)));
-  connect (mp_browser_panel, SIGNAL (url_changed (const QString &)), this, SLOT (title_changed (const QString &)));
+  connect (mp_ui->browser_panel, SIGNAL (title_changed (const QString &)), this, SLOT (title_changed (const QString &)));
+  connect (mp_ui->browser_panel, SIGNAL (url_changed (const QString &)), this, SLOT (title_changed (const QString &)));
 }
 
 HelpDialog::~HelpDialog ()
@@ -82,14 +67,14 @@ void HelpDialog::title_changed (const QString &)
 {
   QString wt;
 
-  QString title = tl::to_qstring (mp_browser_panel->title ());
+  QString title = tl::to_qstring (mp_ui->browser_panel->title ());
   if (title.isNull () || title.size () == 0) {
     wt = m_def_title;
   } else {
     wt = m_def_title + QString::fromUtf8 (" - ") + title;
   }
 
-  QString url = tl::to_qstring (mp_browser_panel->url ());
+  QString url = tl::to_qstring (mp_ui->browser_panel->url ());
   if (! url.isNull () && url.size () > 0) {
     wt += QString::fromUtf8 (" [") + url + QString::fromUtf8 ("]");
   }
@@ -100,13 +85,13 @@ void HelpDialog::title_changed (const QString &)
 void HelpDialog::load (const std::string &url)
 {
   initialize ();
-  mp_browser_panel->load (url);
+  mp_ui->browser_panel->load (url);
 }
 
 void HelpDialog::search (const std::string &topic)
 {
   initialize ();
-  mp_browser_panel->search (topic);
+  mp_ui->browser_panel->search (topic);
 }
 
 void HelpDialog::showEvent (QShowEvent *)
@@ -121,13 +106,13 @@ void HelpDialog::initialize ()
 {
   if (! m_initialized) {
     m_initialized = true;
-    mp_browser_panel->set_search_url ("int:/search.xml", "string");
+    mp_ui->browser_panel->set_search_url ("int:/search.xml", "string");
     if (! mp_help_source) {
       mp_help_source = new lay::HelpSource ();
       tl::StaticObjects::reg (&mp_help_source);
     }
-    mp_browser_panel->set_source (mp_help_source);
-    mp_browser_panel->set_home ("int:/index.xml");
+    mp_ui->browser_panel->set_source (mp_help_source);
+    mp_ui->browser_panel->set_home ("int:/index.xml");
   }
 }
 
diff --git a/src/lay/lay/layHelpDialog.h b/src/lay/lay/layHelpDialog.h
index e24c09d2e..361aed565 100644
--- a/src/lay/lay/layHelpDialog.h
+++ b/src/lay/lay/layHelpDialog.h
@@ -31,6 +31,11 @@
 #include <memory>
 #include <string>
 
+namespace Ui
+{
+  class HelpDialog;
+}
+
 namespace lay
 {
 
@@ -58,7 +63,7 @@ protected slots:
   void title_changed (const QString &t);
 
 private:
-  lay::BrowserPanel *mp_browser_panel;
+  Ui::HelpDialog *mp_ui;
   QRect m_geometry;
   static lay::HelpSource *mp_help_source;
   QString m_def_title;
diff --git a/src/lay/lay/layHelpSource.cc b/src/lay/lay/layHelpSource.cc
index e33569d8b..0b5edd062 100644
--- a/src/lay/lay/layHelpSource.cc
+++ b/src/lay/lay/layHelpSource.cc
@@ -554,6 +554,21 @@ HelpSource::get_outline (const std::string &u)
   return ol;
 }
 
+void
+HelpSource::search_completers (const std::string &string, std::list<std::string> &completers)
+{
+  size_t n = 0;
+  const size_t max_completers = 100;
+
+  //  first produce all hits with match
+  for (std::vector <IndexEntry>::const_iterator i = m_index.begin (); i < m_index.end () && n < max_completers; ++i) {
+    if (i->normalized_key.find (string) != std::string::npos) {
+      completers.push_back (i->key);
+      ++n;
+    }
+  }
+}
+
 std::string
 HelpSource::next_topic (const std::string &url)
 {
diff --git a/src/lay/lay/layHelpSource.h b/src/lay/lay/layHelpSource.h
index dc3af75c2..d355cd2b5 100644
--- a/src/lay/lay/layHelpSource.h
+++ b/src/lay/lay/layHelpSource.h
@@ -82,8 +82,9 @@ public:
   virtual QImage get_image (const std::string &url);
   virtual std::string get_css (const std::string &url);
 
-  virtual std::string next_topic (const std::string &url);
+  virtual void search_completers(const std::string &search_string, std::list<std::string> &completers);
 
+  virtual std::string next_topic (const std::string &url);
   virtual std::string prev_topic (const std::string &url);
 
   QDomDocument get_dom (const std::string &u);
diff --git a/src/lay/lay/layMainConfigPages.cc b/src/lay/lay/layMainConfigPages.cc
index d906a89be..7b982788b 100644
--- a/src/lay/lay/layMainConfigPages.cc
+++ b/src/lay/lay/layMainConfigPages.cc
@@ -61,6 +61,9 @@ public:
     options.push_back (std::pair<std::string, std::string> (cfg_synchronized_views, "false"));
     options.push_back (std::pair<std::string, std::string> (cfg_default_grids, "0.01,0.005,0.001"));
     options.push_back (std::pair<std::string, std::string> (cfg_mru, ""));
+    options.push_back (std::pair<std::string, std::string> (cfg_mru_sessions, ""));
+    options.push_back (std::pair<std::string, std::string> (cfg_mru_layer_properties, ""));
+    options.push_back (std::pair<std::string, std::string> (cfg_mru_bookmarks, ""));
     options.push_back (std::pair<std::string, std::string> (cfg_technologies, ""));
     options.push_back (std::pair<std::string, std::string> (cfg_show_navigator, "false"));
     options.push_back (std::pair<std::string, std::string> (cfg_navigator_all_hier_levels, "false"));
@@ -80,6 +83,7 @@ public:
     options.push_back (std::pair<std::string, std::string> (cfg_micron_digits, "5"));
     options.push_back (std::pair<std::string, std::string> (cfg_dbu_digits, "2"));
     options.push_back (std::pair<std::string, std::string> (cfg_reader_options_show_always, "false"));
+    options.push_back (std::pair<std::string, std::string> (cfg_assistant_bookmarks, ""));
   }
 
   virtual std::vector<std::pair <std::string, ConfigPage *> > config_pages (QWidget *parent) const 
diff --git a/src/lay/lay/layMainWindow.cc b/src/lay/lay/layMainWindow.cc
index 2e8f23f11..425f8485f 100644
--- a/src/lay/lay/layMainWindow.cc
+++ b/src/lay/lay/layMainWindow.cc
@@ -69,9 +69,9 @@
 #include "layConfig.h"
 #include "layMainWindow.h"
 #include "layHelpDialog.h"
-#include "layHelpSource.h" // because of escape_xml
 #include "layNavigator.h"
 #include "layProgress.h"
+#include "layProgressDialog.h"
 #include "layProgressWidget.h"
 #include "layStream.h"
 #include "layLayerControlPanel.h" // because of LabelWithBackground
@@ -89,10 +89,13 @@
 #include "laySaltController.h"
 #include "layTipDialog.h"
 #include "layMacroController.h"
+#include "layHelpAboutDialog.h"
+#include "layControlWidgetStack.h"
+#include "layViewWidgetStack.h"
+#include "layEditorOptionsPages.h"
 #include "layInit.h"
 #include "antObject.h"
 #include "antService.h"
-#include "ui_HelpAboutDialog.h"
 #include "gsi.h"
 #include "gsiInterpreter.h"
 #include "gtf.h"
@@ -104,308 +107,6 @@ const int max_dirty_files = 15;
 
 // -------------------------------------------------------------
 
-class ProgressDialog
-  : public QDialog,
-    public tl::Object
-{
-public:
-  ProgressDialog (QWidget *parent, lay::ProgressReporter *pr)
-    : QDialog (parent), mp_pr (pr)
-  {
-    QVBoxLayout *vbl = new QVBoxLayout (this);
-    vbl->setMargin (0);
-    vbl->setSpacing (0);
-
-    mp_progress_widget = new ProgressWidget (pr, this, true);
-    mp_progress_widget->setObjectName (QString::fromUtf8 ("progress"));
-    vbl->addWidget (mp_progress_widget);
-
-    setWindowTitle (QObject::tr ("Progress"));
-    setWindowModality (Qt::WindowModal);
-  }
-
-  void closeEvent (QCloseEvent * /*event*/)
-  {
-    if (mp_pr) {
-      //  NOTE: We don't kill on close for now. This creates a too easy way to scrap results.
-      //    mp_pr->signal_break ();
-      //  TODO: there should be a warning saying some jobs are pending.
-    }
-  }
-
-  void set_progress (tl::Progress *progress)
-  {
-    mp_progress_widget->set_progress (progress);
-  }
-
-  void add_widget (QWidget *widget)
-  {
-    mp_progress_widget->add_widget (widget);
-  }
-
-  void remove_widget ()
-  {
-    mp_progress_widget->remove_widget ();
-  }
-
-  QWidget *get_widget () const
-  {
-    return mp_progress_widget->get_widget ();
-  }
-
-private:
-  lay::ProgressWidget *mp_progress_widget;
-  lay::ProgressReporter *mp_pr;
-};
-
-// -------------------------------------------------------------
-
-class ControlWidgetStack
-  : public QFrame
-{
-public:
-  ControlWidgetStack (QWidget *parent = 0, const char *name = 0)
-    : QFrame (parent)
-  {
-    setObjectName (QString::fromUtf8 (name));
-
-    //  Background ist a simple label without a text currently
-    mp_bglabel = new QLabel (this);
-    mp_bglabel->setAutoFillBackground (true);
-    mp_bglabel->setAlignment (Qt::AlignVCenter | Qt::AlignHCenter);
-    mp_bglabel->show ();
-  }
-
-  void addWidget (QWidget *w)
-  {
-    m_widgets.push_back (w);
-    w->setParent (this);
-    resize_children ();
-    raiseWidget (m_widgets.size () - 1);
-
-    int mw = 0;
-    for (size_t i = 0; i < m_widgets.size (); ++i) {
-      mw = std::max (m_widgets [i]->sizeHint ().width (), mw);
-      mw = std::max (m_widgets [i]->minimumWidth (), mw);
-    }
-
-    if (mw > minimumWidth ()) {
-      setMinimumWidth (mw);
-      resize (minimumWidth (), height ());
-    }
-  }
-
-  QSize sizeHint () const
-  {
-    int w = 0;
-    for (size_t i = 0; i < m_widgets.size (); ++i) {
-      w = std::max (m_widgets [i]->sizeHint ().width (), w);
-    }
-    return QSize (w, 0);
-  }
-
-  void removeWidget (size_t index)
-  {
-    if (index < m_widgets.size ()) {
-      m_widgets.erase (m_widgets.begin () + index);
-    }
-    if (m_widgets.size () == 0) {
-      mp_bglabel->show ();
-    }
-  }
-
-  void raiseWidget (size_t index)
-  {
-    bool any_visible = false;
-    for (size_t i = 0; i < m_widgets.size (); ++i) {
-      if (m_widgets [i]) {
-        if (i == index) {
-          m_widgets [i]->show ();
-          any_visible = true;
-        } else {
-          m_widgets [i]->hide ();
-        }
-      }
-    }
-
-    if (! any_visible) {
-      mp_bglabel->show ();
-    } else {
-      mp_bglabel->hide ();
-    }
-  }
-
-  QWidget *widget (size_t index)
-  {
-    if (index < m_widgets.size ()) {
-      return m_widgets [index];
-    } else {
-      return 0;
-    }
-  }
-
-  QWidget *background_widget ()
-  {
-    return mp_bglabel;
-  }
-
-protected:
-  virtual void resizeEvent (QResizeEvent *)
-  {
-    resize_children ();
-  }
-
-  void resize_children ()
-  {
-    //  set the geometry of all children
-    for (std::vector <QWidget *>::iterator child = m_widgets.begin (); child != m_widgets.end (); ++child) {
-      if (*child) {
-        (*child)->setGeometry (0, 0, width (), height ());
-      }
-    }
-    mp_bglabel->setGeometry (0, 0, width (), height ());
-  }
-
-  std::vector <QWidget *> m_widgets;
-  QLabel *mp_bglabel;
-};
-
-// -------------------------------------------------------------
-
-class ViewWidgetStack
-  : public QWidget
-{
-public:
-  ViewWidgetStack (QWidget *parent = 0, const char *name = 0)
-    : QWidget (parent)
-  {
-    setObjectName (QString::fromUtf8 (name));
-
-    mp_bglabel = new QLabel (this);
-    mp_bglabel->setAutoFillBackground (true);
-    mp_bglabel->setText (QObject::tr ("<html><body><p><img src=\":/logo.png\"/></p><p>Use File/Open to open a layout</p></body></html>"));
-    mp_bglabel->setAlignment (Qt::AlignVCenter | Qt::AlignHCenter);
-    mp_bglabel->show ();
-  }
-
-  void addWidget (LayoutView *w)
-  {
-    m_widgets.push_back (w);
-    w->setParent (this);
-    resize_children ();
-    raiseWidget (m_widgets.size () - 1);
-
-    updateGeometry ();
-  }
-
-  void removeWidget (size_t index)
-  {
-    if (index < m_widgets.size ()) {
-      m_widgets.erase (m_widgets.begin () + index);
-    }
-    if (m_widgets.size () == 0) {
-      mp_bglabel->show ();
-    }
-  }
-
-  void raiseWidget (size_t index)
-  {
-    if (index < m_widgets.size ()) {
-      mp_bglabel->hide ();
-      m_widgets [index]->show ();
-    } else {
-      mp_bglabel->show ();
-    }
-
-    size_t i = 0;
-    for (std::vector <LayoutView *>::iterator child = m_widgets.begin (); child != m_widgets.end (); ++child, ++i) {
-      if (i != index) {
-        (*child)->hide ();
-      }
-    }
-  }
-
-  LayoutView *widget (size_t index)
-  {
-    if (index < m_widgets.size ()) {
-      return m_widgets [index];
-    } else {
-      return 0;
-    }
-  }
-
-  QWidget *background_widget ()
-  {
-    return mp_bglabel;
-  }
-
-protected:
-  virtual void resizeEvent (QResizeEvent *)
-  {
-    resize_children ();
-  }
-
-  void resize_children ()
-  {
-    //  set the geometry of all children
-    for (std::vector <LayoutView *>::iterator child = m_widgets.begin (); child != m_widgets.end (); ++child) {
-      (*child)->setGeometry (0, 0, width (), height ());
-    }
-    mp_bglabel->setGeometry (0, 0, width (), height ());
-  }
-
-  std::vector <LayoutView *> m_widgets;
-  QLabel *mp_bglabel;
-};
-
-// -------------------------------------------------------------
-
-TextProgressDelegate::TextProgressDelegate (MainWindow *mw, int verbosity)
-  : lay::TextProgress (verbosity), mp_mw (mw)
-{
-  //  .. nothing yet ..
-}
-
-void TextProgressDelegate::update_progress (tl::Progress *progress)
-{
-  if (!mp_mw->update_progress (progress)) {
-    lay::TextProgress::update_progress (progress);
-  }
-}
-
-void TextProgressDelegate::show_progress_bar (bool show)
-{
-  if (!mp_mw->show_progress_bar (show)) {
-    lay::TextProgress::show_progress_bar (show);
-  }
-}
-
-bool TextProgressDelegate::progress_wants_widget () const
-{
-  return mp_mw != 0 && mp_mw->progress_wants_widget ();
-}
-
-void TextProgressDelegate::progress_add_widget (QWidget *widget)
-{
-  if (mp_mw) {
-    mp_mw->progress_add_widget (widget);
-  }
-}
-
-QWidget *TextProgressDelegate::progress_get_widget () const
-{
-  return mp_mw ? mp_mw->progress_get_widget () : 0;
-}
-
-void TextProgressDelegate::progress_remove_widget ()
-{
-  if (mp_mw) {
-    mp_mw->progress_remove_widget ();
-  }
-}
-
-// -------------------------------------------------------------
-
 static MainWindow *mw_instance = 0;
 
 MainWindow *
@@ -414,7 +115,44 @@ MainWindow::instance ()
   return mw_instance;
 }
 
-// -----------------------------------
+// -------------------------------------------------------------
+
+static void
+show_dock_widget (QDockWidget *dock_widget, bool visible)
+{
+  if (visible) {
+
+    dock_widget->show ();
+    dock_widget->setFocus ();
+
+    //  NOTE: this is a clumsy way to make sure the dock widget is made the current tab if it's in a tabbed dock
+    //  TODO: is there a better way to do this?
+    QMainWindow *main_window = dynamic_cast<QMainWindow *> (dock_widget->parent ());
+    if (! main_window) {
+      return;
+    }
+
+    //  Look up all children of the main window and find the QTabBars. These are the dock tabs (we don't create others).
+    //  Inside these, look up the right tab by checking the titles.
+    QList<QObject *> mw_children = main_window->children ();
+    for (QList<QObject *>::const_iterator i = mw_children.begin (); i != mw_children.end (); ++i) {
+      QTabBar *tab_bar = dynamic_cast<QTabBar *> (*i);
+      if (tab_bar) {
+        for (int j = 0; j < tab_bar->count (); ++j) {
+          if (tab_bar->tabText (j) == dock_widget->windowTitle ()) {
+            tab_bar->setCurrentIndex (j);
+            return;
+          }
+        }
+      }
+    }
+
+  } else {
+    dock_widget->hide ();
+  }
+}
+
+// -------------------------------------------------------------
 
 MainWindow::MainWindow (QApplication *app, lay::Plugin *plugin_parent, const char *name, bool undo_enabled)
     : QMainWindow (0),
@@ -426,7 +164,7 @@ MainWindow::MainWindow (QApplication *app, lay::Plugin *plugin_parent, const cha
       m_disable_tab_selected (false),
       m_exited (false),
       dm_do_update_menu (this, &MainWindow::do_update_menu),
-      dm_do_update_file_menu (this, &MainWindow::do_update_file_menu),
+      dm_do_update_mru_menus (this, &MainWindow::do_update_mru_menus),
       dm_exit (this, &MainWindow::exit),
       m_grid_micron (0.001),
       m_default_grids_updated (true),
@@ -455,7 +193,7 @@ MainWindow::MainWindow (QApplication *app, lay::Plugin *plugin_parent, const cha
 
   init_menu ();
 
-  mp_assistant = new lay::HelpDialog (this);
+  mp_assistant = 0;
 
   mp_pr = new lay::ProgressReporter ();
   mp_pr->set_progress_bar (&m_text_progress);
@@ -490,6 +228,7 @@ MainWindow::MainWindow (QApplication *app, lay::Plugin *plugin_parent, const cha
   mp_hp_dock_widget->setObjectName (QString::fromUtf8 ("hp_dock_widget"));
   mp_hp_stack = new ControlWidgetStack (mp_hp_dock_widget, "hp_stack");
   mp_hp_dock_widget->setWidget (mp_hp_stack);
+  mp_hp_dock_widget->setFocusProxy (mp_hp_stack);
   connect (mp_hp_dock_widget, SIGNAL (visibilityChanged (bool)), this, SLOT (dock_widget_visibility_changed (bool)));
   m_hp_visible = true;
 
@@ -497,13 +236,24 @@ MainWindow::MainWindow (QApplication *app, lay::Plugin *plugin_parent, const cha
   mp_libs_dock_widget->setObjectName (QString::fromUtf8 ("libs_dock_widget"));
   mp_libs_stack = new ControlWidgetStack (mp_libs_dock_widget, "libs_stack");
   mp_libs_dock_widget->setWidget (mp_libs_stack);
+  mp_libs_dock_widget->setFocusProxy (mp_libs_stack);
   connect (mp_libs_dock_widget, SIGNAL (visibilityChanged (bool)), this, SLOT (dock_widget_visibility_changed (bool)));
   m_libs_visible = true;
 
+  mp_eo_dock_widget = new QDockWidget (QObject::tr ("Editor Options"), this);
+  mp_eo_dock_widget->setObjectName (QString::fromUtf8 ("eo_dock_widget"));
+  mp_eo_dock_widget->setMinimumHeight (150);
+  mp_eo_stack = new ControlWidgetStack (mp_eo_dock_widget, "eo_stack");
+  mp_eo_dock_widget->setWidget (mp_eo_stack);
+  mp_eo_dock_widget->setFocusProxy (mp_eo_stack);
+  connect (mp_eo_dock_widget, SIGNAL (visibilityChanged (bool)), this, SLOT (dock_widget_visibility_changed (bool)));
+  m_eo_visible = true;
+
   mp_bm_dock_widget = new QDockWidget (QObject::tr ("Bookmarks"), this);
   mp_bm_dock_widget->setObjectName (QString::fromUtf8 ("bookmarks_dock_widget"));
   mp_bm_stack = new ControlWidgetStack (mp_bm_dock_widget, "bookmarks_stack");
   mp_bm_dock_widget->setWidget (mp_bm_stack);
+  mp_bm_dock_widget->setFocusProxy (mp_bm_stack);
   connect (mp_bm_dock_widget, SIGNAL (visibilityChanged (bool)), this, SLOT (dock_widget_visibility_changed (bool)));
   m_bm_visible = true;
 
@@ -515,6 +265,7 @@ MainWindow::MainWindow (QApplication *app, lay::Plugin *plugin_parent, const cha
   mp_layer_toolbox_dock_widget->setObjectName (QString::fromUtf8 ("lt_dock_widget"));
   mp_layer_toolbox = new LayerToolbox (mp_layer_toolbox_dock_widget, "layer_toolbox");
   mp_layer_toolbox_dock_widget->setWidget (mp_layer_toolbox);
+  mp_layer_toolbox_dock_widget->setFocusProxy (mp_layer_toolbox);
   connect (mp_layer_toolbox_dock_widget, SIGNAL (visibilityChanged (bool)), this, SLOT (dock_widget_visibility_changed (bool)));
   m_layer_toolbox_visible = true;
 
@@ -522,6 +273,7 @@ MainWindow::MainWindow (QApplication *app, lay::Plugin *plugin_parent, const cha
   mp_lp_dock_widget->setObjectName (QString::fromUtf8 ("lp_dock_widget"));
   mp_lp_stack = new ControlWidgetStack (mp_lp_dock_widget, "lp_stack");
   mp_lp_dock_widget->setWidget (mp_lp_stack);
+  mp_lp_dock_widget->setFocusProxy (mp_lp_stack);
   connect (mp_lp_dock_widget, SIGNAL (visibilityChanged (bool)), this, SLOT (dock_widget_visibility_changed (bool)));
   m_lp_visible = true;
 
@@ -529,6 +281,7 @@ MainWindow::MainWindow (QApplication *app, lay::Plugin *plugin_parent, const cha
   mp_navigator_dock_widget->setObjectName (QString::fromUtf8 ("navigator_dock_widget"));
   mp_navigator = new Navigator (this);
   mp_navigator_dock_widget->setWidget (mp_navigator);
+  mp_navigator_dock_widget->setFocusProxy (mp_navigator);
   connect (mp_navigator_dock_widget, SIGNAL (visibilityChanged (bool)), this, SLOT (dock_widget_visibility_changed (bool)));
   m_navigator_visible = true;
 
@@ -539,6 +292,7 @@ MainWindow::MainWindow (QApplication *app, lay::Plugin *plugin_parent, const cha
   addDockWidget(Qt::LeftDockWidgetArea, mp_navigator_dock_widget);
   addDockWidget(Qt::LeftDockWidgetArea, mp_hp_dock_widget);
   addDockWidget(Qt::LeftDockWidgetArea, mp_libs_dock_widget);
+  addDockWidget(Qt::LeftDockWidgetArea, mp_eo_dock_widget);
   addDockWidget(Qt::RightDockWidgetArea, mp_bm_dock_widget);
   addDockWidget(Qt::RightDockWidgetArea, mp_lp_dock_widget);
   addDockWidget(Qt::RightDockWidgetArea, mp_layer_toolbox_dock_widget);
@@ -750,7 +504,7 @@ MainWindow::init_menu ()
 }
 
 void
-MainWindow::dock_widget_visibility_changed (bool /*visible*/)
+MainWindow::dock_widget_visibility_changed (bool visible)
 {
   if (sender () == mp_lp_dock_widget) {
     dispatcher ()->config_set (cfg_show_layer_panel, tl::to_string (!mp_lp_dock_widget->isHidden ()));
@@ -764,6 +518,8 @@ MainWindow::dock_widget_visibility_changed (bool /*visible*/)
     dispatcher ()->config_set (cfg_show_navigator, tl::to_string (!mp_navigator_dock_widget->isHidden ()));
   } else if (sender () == mp_layer_toolbox_dock_widget) {
     dispatcher ()->config_set (cfg_show_layer_toolbox, tl::to_string (!mp_layer_toolbox_dock_widget->isHidden ()));
+  } else if (sender () == mp_eo_dock_widget) {
+    m_eo_visible = visible;
   }
 }
 
@@ -892,6 +648,7 @@ MainWindow::show ()
 void
 MainWindow::close_all ()
 {
+  cancel ();
   mp_layer_toolbox->set_view (0);
 
   //  try a smooth shutdown of the current view
@@ -922,11 +679,12 @@ MainWindow::close_all ()
 
     lay::LayoutView *view = mp_views.back ();
     mp_views.pop_back ();
-    mp_lp_stack->removeWidget (mp_views.size ());
-    mp_hp_stack->removeWidget (mp_views.size ());
-    mp_libs_stack->removeWidget (mp_views.size ());
-    mp_bm_stack->removeWidget (mp_views.size ());
-    mp_view_stack->removeWidget (mp_views.size ());
+    mp_lp_stack->remove_widget (mp_views.size ());
+    mp_hp_stack->remove_widget (mp_views.size ());
+    mp_libs_stack->remove_widget (mp_views.size ());
+    mp_eo_stack->remove_widget (mp_views.size ());
+    mp_bm_stack->remove_widget (mp_views.size ());
+    mp_view_stack->remove_widget (mp_views.size ());
 
     delete view;
 
@@ -1103,9 +861,18 @@ MainWindow::config_finalize ()
   // Not set the window state: this ensures we have handled cfg_window_geometry
   // before we restore the state
   if (! m_config_window_state.empty ()) {
+
     QByteArray state = QByteArray::fromBase64 (m_config_window_state.c_str ());
     m_config_window_state.clear ();
+
+    bool eo_visible = m_eo_visible;
+
     restoreState (state);
+
+    //  Keep the editor options visibility state
+    m_eo_visible = eo_visible;
+    show_dock_widget (mp_eo_dock_widget, m_eo_visible);
+
   }
 
   // Update the default grids menu if necessary
@@ -1258,7 +1025,49 @@ MainWindow::configure (const std::string &name, const std::string &value)
       }
     }
 
-    dm_do_update_file_menu ();
+    dm_do_update_mru_menus ();
+
+    return true;
+
+  } else if (name == cfg_mru_sessions) {
+
+    tl::Extractor ex (value.c_str ());
+
+    m_mru_sessions.clear ();
+    while (! ex.at_end ()) {
+      m_mru_sessions.push_back (value);
+      ex.read_quoted (m_mru_sessions.back ());
+    }
+
+    dm_do_update_mru_menus ();
+
+    return true;
+
+  } else if (name == cfg_mru_layer_properties) {
+
+    tl::Extractor ex (value.c_str ());
+
+    m_mru_layer_properties.clear ();
+    while (! ex.at_end ()) {
+      m_mru_layer_properties.push_back (value);
+      ex.read_quoted (m_mru_layer_properties.back ());
+    }
+
+    dm_do_update_mru_menus ();
+
+    return true;
+
+  } else if (name == cfg_mru_bookmarks) {
+
+    tl::Extractor ex (value.c_str ());
+
+    m_mru_bookmarks.clear ();
+    while (! ex.at_end ()) {
+      m_mru_bookmarks.push_back (value);
+      ex.read_quoted (m_mru_bookmarks.back ());
+    }
+
+    dm_do_update_mru_menus ();
 
     return true;
 
@@ -1518,6 +1327,12 @@ MainWindow::update_dock_widget_state ()
     mp_libs_dock_widget->hide ();
   }
 
+  if (m_eo_visible) {
+    mp_eo_dock_widget->show ();
+  } else {
+    mp_eo_dock_widget->hide ();
+  }
+
   if (m_bm_visible) {
     mp_bm_dock_widget->show ();
   } else {
@@ -1856,6 +1671,32 @@ MainWindow::select_mode (int m)
       }
     }
 
+    //  if the current mode supports editing, show the editor options panel
+
+    const lay::PluginDeclaration *pd_sel = 0;
+    for (tl::Registrar<lay::PluginDeclaration>::iterator cls = tl::Registrar<lay::PluginDeclaration>::begin (); cls != tl::Registrar<lay::PluginDeclaration>::end (); ++cls) {
+      const lay::PluginDeclaration *pd = cls.operator-> ();
+      if (pd->id () == m_mode) {
+        pd_sel = pd;
+      }
+    }
+
+    bool eo_visible = false;
+    if (mp_eo_stack && pd_sel) {
+      eo_visible = pd_sel->editable_enabled ();
+    }
+    if (current_view () && eo_visible) {
+      lay::EditorOptionsPages *eo_pages = current_view ()->editor_options_pages ();
+      if (! eo_pages || ! eo_pages->has_content ()) {
+        eo_visible = false;
+      }
+    }
+
+    if (eo_visible != m_eo_visible) {
+      m_eo_visible = eo_visible;
+      show_dock_widget (mp_eo_dock_widget, m_eo_visible);
+    }
+
   }
 }
 
@@ -2147,6 +1988,7 @@ MainWindow::cm_save_layer_props ()
     std::string fn;
     if (mp_lprops_fdia->get_save (fn, tl::to_string (QObject::tr ("Save Layer Properties File")))) {
       current_view ()->save_layer_props (fn);
+      add_to_other_mru (fn, cfg_mru_layer_properties);
     }
   } else {
     throw tl::Exception (tl::to_string (QObject::tr ("No view open to save the layer properties from")));
@@ -2189,6 +2031,8 @@ MainWindow::cm_load_layer_props ()
         load_layer_properties (fn, false /*current view only*/, false /*don't add default*/);
       }
 
+      add_to_other_mru (fn, cfg_mru_layer_properties);
+
     }
   } else {
     throw tl::Exception (tl::to_string (QObject::tr ("No view open to load the layer properties for")));
@@ -2230,6 +2074,7 @@ MainWindow::cm_save_session ()
     std::string fn = m_current_session;
     if (mp_session_fdia->get_save (fn, tl::to_string (QObject::tr ("Save Session File")))) {
       save_session (fn);
+      add_to_other_mru (fn, cfg_mru_sessions);
     }
 
   }
@@ -2245,7 +2090,10 @@ MainWindow::cm_restore_session ()
     int dirty_layouts = dirty_files (df_list);
 
     if (dirty_layouts == 0) {
+
       restore_session (fn);
+      add_to_other_mru (fn, cfg_mru_sessions);
+
     } else {
 
       QMessageBox mbox (this);
@@ -2259,6 +2107,7 @@ MainWindow::cm_restore_session ()
 
       if (mbox.clickedButton() == discard_button) {
         restore_session (fn);
+        add_to_other_mru (fn, cfg_mru_sessions);
       }
 
     }
@@ -2273,6 +2122,7 @@ MainWindow::cm_save_bookmarks ()
     std::string fn;
     if (mp_bookmarks_fdia->get_save (fn, tl::to_string (QObject::tr ("Save Bookmarks File")))) {
       current_view ()->bookmarks ().save (fn);
+      add_to_other_mru (fn, cfg_mru_bookmarks);
     }
   } else {
     throw tl::Exception (tl::to_string (QObject::tr ("No view open to save the bookmarks from")));
@@ -2288,6 +2138,7 @@ MainWindow::cm_load_bookmarks ()
       BookmarkList bookmarks;
       bookmarks.load (fn);
       current_view ()->bookmarks (bookmarks);
+      add_to_other_mru (fn, cfg_mru_bookmarks);
     }
   } else {
     throw tl::Exception (tl::to_string (QObject::tr ("No view open to load the bookmarks for")));
@@ -2502,6 +2353,8 @@ MainWindow::select_view (int index)
 
   try {
 
+    cancel ();
+
     tl_assert (index >= 0 && index < int (views ()));
 
     mp_tab_bar->setCurrentIndex (index);
@@ -2522,11 +2375,12 @@ MainWindow::select_view (int index)
         current_view ()->zoom_box (box);
       }
 
-      mp_view_stack->raiseWidget (index);
-      mp_hp_stack->raiseWidget (index);
-      mp_lp_stack->raiseWidget (index);
-      mp_libs_stack->raiseWidget (index);
-      mp_bm_stack->raiseWidget (index);
+      mp_view_stack->raise_widget (index);
+      mp_hp_stack->raise_widget (index);
+      mp_lp_stack->raise_widget (index);
+      mp_libs_stack->raise_widget (index);
+      mp_eo_stack->raise_widget (index);
+      mp_bm_stack->raise_widget (index);
       mp_setup_form->setup ();
 
     }
@@ -2713,11 +2567,12 @@ MainWindow::clone_current_view ()
 
   mp_layer_toolbox->set_view (current_view ());
 
-  mp_view_stack->addWidget (view);
-  mp_lp_stack->addWidget (view->layer_control_frame ());
-  mp_hp_stack->addWidget (view->hierarchy_control_frame ());
-  mp_libs_stack->addWidget (view->libraries_frame ());
-  mp_bm_stack->addWidget (view->bookmarks_frame ());
+  mp_view_stack->add_widget (view);
+  mp_lp_stack->add_widget (view->layer_control_frame ());
+  mp_hp_stack->add_widget (view->hierarchy_control_frame ());
+  mp_libs_stack->add_widget (view->libraries_frame ());
+  mp_eo_stack->add_widget (view->editor_options_frame ());
+  mp_bm_stack->add_widget (view->bookmarks_frame ());
 
   bool f = m_disable_tab_selected;
   m_disable_tab_selected = true;
@@ -2949,6 +2804,8 @@ MainWindow::close_view (int index)
 {
   if (view (index)) {
 
+    cancel ();
+
     //  this suppresses view_selected events that would otherwise be created
     bool f = m_disable_tab_selected;
     m_disable_tab_selected = true;
@@ -2961,11 +2818,12 @@ MainWindow::close_view (int index)
       }
 
       mp_tab_bar->removeTab (index);
-      mp_view_stack->removeWidget (index);
-      mp_lp_stack->removeWidget (index);
-      mp_hp_stack->removeWidget (index);
-      mp_libs_stack->removeWidget (index);
-      mp_bm_stack->removeWidget (index);
+      mp_view_stack->remove_widget (index);
+      mp_lp_stack->remove_widget (index);
+      mp_hp_stack->remove_widget (index);
+      mp_libs_stack->remove_widget (index);
+      mp_eo_stack->remove_widget (index);
+      mp_bm_stack->remove_widget (index);
 
       view_closed_event (int (index));
 
@@ -3009,6 +2867,8 @@ MainWindow::add_mru (const std::string &fn_rel)
   add_mru (fn_rel, m_initial_technology);
 }
 
+const size_t max_mru = 16;
+
 void
 MainWindow::add_mru (const std::string &fn_rel, const std::string &tech)
 {
@@ -3024,7 +2884,7 @@ MainWindow::add_mru (const std::string &fn_rel, const std::string &tech)
 
   new_mru.push_back (std::make_pair (fn, tech));
 
-  if (new_mru.size () > 10) {
+  if (new_mru.size () > max_mru) {
     new_mru.erase (new_mru.begin ());
   }
 
@@ -3043,6 +2903,47 @@ MainWindow::add_mru (const std::string &fn_rel, const std::string &tech)
   dispatcher ()->config_set (cfg_mru, config_str);
 }
 
+void
+MainWindow::add_to_other_mru (const std::string &fn_rel, const std::string &cfg)
+{
+  std::vector <std::string> *mru_ptr;
+  if (cfg == cfg_mru_sessions) {
+    mru_ptr = &m_mru_sessions;
+  } else if (cfg == cfg_mru_layer_properties) {
+    mru_ptr = &m_mru_layer_properties;
+  } else if (cfg == cfg_mru_bookmarks) {
+    mru_ptr = &m_mru_bookmarks;
+  } else {
+    tl_assert (false);
+  }
+
+  std::vector <std::string> new_mru = *mru_ptr;
+  std::string fn (tl::InputStream::absolute_path (fn_rel));
+
+  for (std::vector<std::string>::iterator mru = new_mru.begin (); mru != new_mru.end (); ++mru) {
+    if (*mru == fn) {
+      new_mru.erase (mru);
+      break;
+    }
+  }
+
+  new_mru.push_back (fn);
+
+  if (new_mru.size () > max_mru) {
+    new_mru.erase (new_mru.begin ());
+  }
+
+  std::string config_str;
+  for (std::vector<std::string>::const_iterator mru = new_mru.begin (); mru != new_mru.end (); ++mru) {
+    if (! config_str.empty ()) {
+      config_str += " ";
+    }
+    config_str += tl::to_quoted_string (*mru);
+  }
+
+  dispatcher ()->config_set (cfg, config_str);
+}
+
 namespace
 {
 
@@ -3064,10 +2965,64 @@ private:
   size_t m_n;
 };
 
+class OpenRecentSessionAction
+  : public lay::Action
+{
+public:
+  OpenRecentSessionAction (lay::MainWindow *mw, size_t n)
+    : lay::Action (), mp_mw (mw), m_n (n)
+  { }
+
+  void triggered ()
+  {
+    mp_mw->open_recent_session (m_n);
+  }
+
+private:
+  lay::MainWindow *mp_mw;
+  size_t m_n;
+};
+
+class OpenRecentLayerPropertiesAction
+  : public lay::Action
+{
+public:
+  OpenRecentLayerPropertiesAction (lay::MainWindow *mw, size_t n)
+    : lay::Action (), mp_mw (mw), m_n (n)
+  { }
+
+  void triggered ()
+  {
+    mp_mw->open_recent_layer_properties (m_n);
+  }
+
+private:
+  lay::MainWindow *mp_mw;
+  size_t m_n;
+};
+
+class OpenRecentBookmarksAction
+  : public lay::Action
+{
+public:
+  OpenRecentBookmarksAction (lay::MainWindow *mw, size_t n)
+    : lay::Action (), mp_mw (mw), m_n (n)
+  { }
+
+  void triggered ()
+  {
+    mp_mw->open_recent_bookmarks (m_n);
+  }
+
+private:
+  lay::MainWindow *mp_mw;
+  size_t m_n;
+};
+
 }
 
 void
-MainWindow::do_update_file_menu ()
+MainWindow::do_update_mru_menus ()
 {
   std::string mru_menu = "file_menu.open_recent_menu";
 
@@ -3094,6 +3049,84 @@ MainWindow::do_update_file_menu ()
     }
 
   }
+
+  mru_menu = "file_menu.open_recent_menu_sessions";
+
+  if (menu ()->is_valid (mru_menu)) {
+
+    Action *open_recent_action = menu ()->action (mru_menu);
+    open_recent_action->set_enabled (true);
+
+    if (m_mru_sessions.size () > 0 && edits_enabled ()) {
+
+      //  rebuild MRU menu
+      menu ()->clear_menu (mru_menu);
+
+      for (std::vector<std::string>::iterator mru = m_mru_sessions.end (); mru != m_mru_sessions.begin (); ) {
+        --mru;
+        size_t i = std::distance (m_mru_sessions.begin (), mru);
+        Action *action = new OpenRecentSessionAction (this, i);
+        action->set_title (*mru);
+        menu ()->insert_item (mru_menu + ".end", tl::sprintf ("open_recent_%d", i + 1), action);
+      }
+
+    } else {
+      open_recent_action->set_enabled (false);
+    }
+
+  }
+
+  mru_menu = "file_menu.open_recent_menu_layer_props";
+
+  if (menu ()->is_valid (mru_menu)) {
+
+    Action *open_recent_action = menu ()->action (mru_menu);
+    open_recent_action->set_enabled (true);
+
+    if (m_mru_layer_properties.size () > 0 && edits_enabled ()) {
+
+      //  rebuild MRU menu
+      menu ()->clear_menu (mru_menu);
+
+      for (std::vector<std::string>::iterator mru = m_mru_layer_properties.end (); mru != m_mru_layer_properties.begin (); ) {
+        --mru;
+        size_t i = std::distance (m_mru_layer_properties.begin (), mru);
+        Action *action = new OpenRecentLayerPropertiesAction (this, i);
+        action->set_title (*mru);
+        menu ()->insert_item (mru_menu + ".end", tl::sprintf ("open_recent_%d", i + 1), action);
+      }
+
+    } else {
+      open_recent_action->set_enabled (false);
+    }
+
+  }
+
+  mru_menu = "bookmark_menu.open_recent_menu_bookmarks";
+
+  if (menu ()->is_valid (mru_menu)) {
+
+    Action *open_recent_action = menu ()->action (mru_menu);
+    open_recent_action->set_enabled (true);
+
+    if (m_mru_bookmarks.size () > 0 && edits_enabled ()) {
+
+      //  rebuild MRU menu
+      menu ()->clear_menu (mru_menu);
+
+      for (std::vector<std::string>::iterator mru = m_mru_bookmarks.end (); mru != m_mru_bookmarks.begin (); ) {
+        --mru;
+        size_t i = std::distance (m_mru_bookmarks.begin (), mru);
+        Action *action = new OpenRecentBookmarksAction (this, i);
+        action->set_title (*mru);
+        menu ()->insert_item (mru_menu + ".end", tl::sprintf ("open_recent_%d", i + 1), action);
+      }
+
+    } else {
+      open_recent_action->set_enabled (false);
+    }
+
+  }
 }
 
 void
@@ -3150,6 +3183,52 @@ MainWindow::open_recent (size_t n)
   END_PROTECTED
 }
 
+void
+MainWindow::open_recent_session (size_t n)
+{
+  BEGIN_PROTECTED
+
+  if (n < m_mru_sessions.size ()) {
+    std::string fn = m_mru_sessions [n];
+    restore_session (fn);
+    add_to_other_mru (fn, cfg_mru_sessions);  //  make it the latest
+  }
+
+  END_PROTECTED
+}
+
+void
+MainWindow::open_recent_layer_properties (size_t n)
+{
+  BEGIN_PROTECTED
+
+  if (n < m_mru_layer_properties.size ()) {
+    std::string fn = m_mru_layer_properties [n];
+    load_layer_properties (fn, false /*current view only*/, false /*don't add default*/);
+    add_to_other_mru (fn, cfg_mru_layer_properties);  //  make it the latest
+  }
+
+  END_PROTECTED
+}
+
+void
+MainWindow::open_recent_bookmarks (size_t n)
+{
+  BEGIN_PROTECTED
+
+  if (n < m_mru_bookmarks.size ()) {
+    std::string fn = m_mru_bookmarks [n];
+    if (current_view ()) {
+      BookmarkList bookmarks;
+      bookmarks.load (fn);
+      current_view ()->bookmarks (bookmarks);
+      add_to_other_mru (fn, cfg_mru_bookmarks);
+    }
+  }
+
+  END_PROTECTED
+}
+
 void
 MainWindow::open (int mode)
 {
@@ -3282,11 +3361,12 @@ MainWindow::create_view ()
 
   mp_layer_toolbox->set_view (current_view ());
 
-  mp_view_stack->addWidget (mp_views.back ());
-  mp_lp_stack->addWidget (mp_views.back ()->layer_control_frame ());
-  mp_hp_stack->addWidget (mp_views.back ()->hierarchy_control_frame ());
-  mp_libs_stack->addWidget (mp_views.back ()->libraries_frame ());
-  mp_bm_stack->addWidget (mp_views.back ()->bookmarks_frame ());
+  mp_view_stack->add_widget (mp_views.back ());
+  mp_lp_stack->add_widget (mp_views.back ()->layer_control_frame ());
+  mp_hp_stack->add_widget (mp_views.back ()->hierarchy_control_frame ());
+  mp_libs_stack->add_widget (mp_views.back ()->libraries_frame ());
+  mp_eo_stack->add_widget (mp_views.back ()->editor_options_frame ());
+  mp_bm_stack->add_widget (mp_views.back ()->bookmarks_frame ());
 
   bool f = m_disable_tab_selected;
   m_disable_tab_selected = true;
@@ -3345,11 +3425,12 @@ MainWindow::create_or_load_layout (const std::string *filename, const db::LoadLa
 
       mp_layer_toolbox->set_view (current_view ());
 
-      mp_view_stack->addWidget (mp_views.back ());
-      mp_lp_stack->addWidget (mp_views.back ()->layer_control_frame ());
-      mp_hp_stack->addWidget (mp_views.back ()->hierarchy_control_frame ());
-      mp_libs_stack->addWidget (mp_views.back ()->libraries_frame ());
-      mp_bm_stack->addWidget (mp_views.back ()->bookmarks_frame ());
+      mp_view_stack->add_widget (mp_views.back ());
+      mp_lp_stack->add_widget (mp_views.back ()->layer_control_frame ());
+      mp_hp_stack->add_widget (mp_views.back ()->hierarchy_control_frame ());
+      mp_libs_stack->add_widget (mp_views.back ()->libraries_frame ());
+      mp_eo_stack->add_widget (mp_views.back ()->editor_options_frame ());
+      mp_bm_stack->add_widget (mp_views.back ()->bookmarks_frame ());
 
       bool f = m_disable_tab_selected;
       m_disable_tab_selected = true;
@@ -3641,6 +3722,10 @@ MainWindow::cm_macro_editor ()
 void
 MainWindow::cm_show_assistant ()
 {
+  if (! mp_assistant) {
+    mp_assistant = new lay::HelpDialog (this);
+  }
+
   if (mp_assistant->isMinimized ()) {
     mp_assistant->showNormal ();
   } else {
@@ -3676,13 +3761,7 @@ MainWindow::show_assistant_url (const std::string &url, bool modal)
 
   } else {
 
-    if (mp_assistant->isMinimized ()) {
-      mp_assistant->showNormal ();
-    } else {
-      mp_assistant->show ();
-    }
-    mp_assistant->activateWindow ();
-    mp_assistant->raise ();
+    cm_show_assistant ();
     mp_assistant->load (url);
 
   }
@@ -3699,13 +3778,7 @@ MainWindow::show_assistant_topic (const std::string &s, bool modal)
 
   } else {
 
-    if (mp_assistant->isMinimized ()) {
-      mp_assistant->showNormal ();
-    } else {
-      mp_assistant->show ();
-    }
-    mp_assistant->activateWindow ();
-    mp_assistant->raise ();
+    cm_show_assistant ();
     mp_assistant->search (s);
 
   }
@@ -3824,6 +3897,11 @@ MainWindow::menu_activated (const std::string &symbol)
     cm_help_about ();
   } else if (symbol == "cm_help_about_qt") {
     cm_help_about_qt ();
+  } else if (symbol == "cm_edit_options") {
+
+    m_eo_visible = true;
+    show_dock_widget (mp_eo_dock_widget, m_eo_visible);
+
   } else {
 
     //  Try the plugin declarations
@@ -3978,10 +4056,12 @@ MainWindow::dropEvent(QDropEvent *event)
       if (suffix == QString::fromUtf8 ("lyp")) {
 
         load_layer_properties (tl::to_string (path), false /*current view only*/, false /*don't add a default*/);
+        add_to_other_mru (tl::to_string (path), cfg_mru_layer_properties);
 
       } else if (suffix == QString::fromUtf8 ("lys")) {
 
         restore_session (tl::to_string (path));
+        add_to_other_mru (tl::to_string (path), cfg_mru_sessions);
 
       } else if (suffix == QString::fromUtf8 ("lyb")) {
 
@@ -3989,6 +4069,7 @@ MainWindow::dropEvent(QDropEvent *event)
           BookmarkList bookmarks;
           bookmarks.load (tl::to_string (path));
           current_view ()->bookmarks (bookmarks);
+          add_to_other_mru (tl::to_string (path), cfg_mru_bookmarks);
         }
 
       } else {
@@ -4063,108 +4144,6 @@ MainWindow::plugin_removed (lay::PluginDeclaration *cls)
   }
 }
 
-// ------------------------------------------------------------
-//  Implementation of the "help about" dialog
-
-HelpAboutDialog::HelpAboutDialog (QWidget *parent)
-  : QDialog (parent)
-{
-  mp_ui = new Ui::HelpAboutDialog ();
-  mp_ui->setupUi (this);
-
-  std::vector<std::string> build_options;
-  if (lay::ApplicationBase::instance ()->ruby_interpreter ().available ()) {
-    build_options.push_back (tl::to_string (tr ("Ruby interpreter ")) + lay::ApplicationBase::instance ()->ruby_interpreter ().version ());
-  }
-  if (lay::ApplicationBase::instance ()->python_interpreter ().available ()) {
-    build_options.push_back (tl::to_string (tr ("Python interpreter ")) + lay::ApplicationBase::instance ()->python_interpreter ().version ());
-  }
-#if defined(HAVE_QTBINDINGS)
-  build_options.push_back (tl::to_string (tr ("Qt bindings for scripts")));
-#endif
-#if defined(HAVE_64BIT_COORD)
-  build_options.push_back (tl::to_string (tr ("Wide coordinates (64 bit)")));
-#endif
-
-  std::string s;
-
-  s = "<html><body>";
-
-  s += "<h1>";
-  s += escape_xml (std::string (lay::Version::name ()) + " " + lay::Version::version ());
-  s += "</h1>";
-
-  std::vector<std::string> about_paras = tl::split (lay::Version::about_text (), "\n\n");
-  for (std::vector<std::string>::const_iterator p = about_paras.begin (); p != about_paras.end (); ++p) {
-    s += std::string ("<p>") + escape_xml (*p) + "</p>";
-  }
-
-  if (! build_options.empty ()) {
-    s += "<p>";
-    s += "<h4>";
-    s += escape_xml (tl::to_string (QObject::tr ("Build options:")));
-    s += "</h4><ul>";
-    for (std::vector<std::string>::const_iterator bo = build_options.begin (); bo != build_options.end (); ++bo) {
-      s += "<li>";
-      s += escape_xml (*bo);
-      s += "</li>";
-    }
-    s += "</ul>";
-  }
-
-  if (! lay::plugins ().empty () || ! db::plugins ().empty ()) {
-
-    s += "<p>";
-    s += "<h4>";
-    s += escape_xml (tl::to_string (QObject::tr ("Binary extensions:")));
-    s += "</h4><ul>";
-
-    for (std::list<lay::PluginDescriptor>::const_iterator pd = lay::plugins ().begin (); pd != lay::plugins ().end (); ++pd) {
-      s += "<li>";
-      if (! pd->description.empty ()) {
-        s += escape_xml (pd->description);
-      } else {
-        s += escape_xml (pd->path);
-      }
-      if (! pd->version.empty ()) {
-        s += " (" + escape_xml (pd->version) + ")";
-      }
-      s += "</li>";
-    }
-
-    for (std::list<db::PluginDescriptor>::const_iterator pd = db::plugins ().begin (); pd != db::plugins ().end (); ++pd) {
-      s += "<li>";
-      if (! pd->description.empty ()) {
-        s += escape_xml (pd->description);
-      } else {
-        s += escape_xml (pd->path);
-      }
-      if (! pd->version.empty ()) {
-        s += " (" + escape_xml (pd->version) + ")";
-      }
-      s += "</li>";
-    }
-
-    s += "</ul>";
-
-  }
-
-  s += "</body></html>";
-
-  std::string t = tl::to_string (QObject::tr ("About ")) + lay::Version::name ();
-
-  setWindowTitle (tl::to_qstring (t));
-
-  mp_ui->main->setWordWrap (true);
-  mp_ui->main->setText (tl::to_qstring (s));
-}
-
-HelpAboutDialog::~HelpAboutDialog ()
-{
-  delete mp_ui;
-  mp_ui = 0;
-}
-
 // ------------------------------------------------------------
 //  Declaration of the "plugin" for the menu entries
 
@@ -4189,6 +4168,10 @@ public:
     menu_entries.push_back (lay::submenu ("@secrets", at, tl::to_string (QObject::tr ("Secret Features"))));
     menu_entries.push_back (lay::submenu ("@toolbar", at, std::string ()));
 
+    at = "edit_menu.end";
+    menu_entries.push_back (lay::separator ("edit_options_group:edit_mode", "edit_menu.end"));
+    menu_entries.push_back (lay::menu_item ("cm_edit_options", "edit_options:edit_mode", "edit_menu.end", tl::to_string (QObject::tr ("Editor Options")) + "(F3)"));
+
     at = "file_menu.end";
     menu_entries.push_back (lay::menu_item ("cm_new_layout", "new_layout:edit:edit_mode", at, tl::to_string (QObject::tr ("New Layout"))));
     menu_entries.push_back (lay::menu_item ("cm_new_panel", "new_panel:edit:edit_mode", at, tl::to_string (QObject::tr ("New Panel"))));
@@ -4220,9 +4203,11 @@ public:
     menu_entries.push_back (lay::separator ("layer_group", at));
     menu_entries.push_back (lay::menu_item ("cm_load_layer_props", "load_layer_props:edit", at, tl::to_string (QObject::tr ("Load Layer Properties"))));
     menu_entries.push_back (lay::menu_item ("cm_save_layer_props", "save_layer_props:edit", at, tl::to_string (QObject::tr ("Save Layer Properties"))));
+    menu_entries.push_back (lay::submenu ("open_recent_menu_layer_props:edit", at, tl::to_string (QObject::tr ("Recent Layer Properties"))));
     menu_entries.push_back (lay::separator ("session_group", at));
     menu_entries.push_back (lay::menu_item ("cm_restore_session", "restore_session:edit", at, tl::to_string (QObject::tr ("Restore Session"))));
     menu_entries.push_back (lay::menu_item ("cm_save_session", "save_session", at, tl::to_string (QObject::tr ("Save Session"))));
+    menu_entries.push_back (lay::submenu ("open_recent_menu_sessions:edit", at, tl::to_string (QObject::tr ("Recent Sessions"))));
     menu_entries.push_back (lay::separator ("log_group", at));
     menu_entries.push_back (lay::menu_item ("cm_view_log", "view_log", at, tl::to_string (QObject::tr ("Log Viewer"))));
     menu_entries.push_back (lay::separator ("print_group", at));
@@ -4251,6 +4236,7 @@ public:
     menu_entries.push_back (lay::menu_item ("cm_reset_window_state", "reset_window_state", at, tl::to_string (QObject::tr ("Restore Window")))),
     menu_entries.push_back (lay::separator ("selection_group", at));
     menu_entries.push_back (lay::config_menu_item ("transient_selection", at, tl::to_string (QObject::tr ("Highlight Object Under Mouse")), cfg_sel_transient_mode, "?"));
+    menu_entries.push_back (lay::config_menu_item ("mouse_tracking", at, tl::to_string (QObject::tr ("Mouse tracking")), cfg_tracking_cursor_enabled, "?"));
 
     at = "help_menu.end";
     menu_entries.push_back (lay::menu_item ("cm_show_all_tips", "show_all_tips", at, tl::to_string (QObject::tr ("Show All Tips"))));
@@ -4270,8 +4256,8 @@ public:
     menu_entries.push_back (lay::separator ("macros_group", at));
 
     at = "@toolbar.end";
-    menu_entries.push_back (lay::menu_item ("cm_prev_display_state", "prev_display_state", at, tl::to_string (QObject::tr ("Back(Shift+Tab)<:/back.png>"))));
-    menu_entries.push_back (lay::menu_item ("cm_next_display_state", "next_display_state", at, tl::to_string (QObject::tr ("Forward(Tab)<:/forward.png>"))));
+    menu_entries.push_back (lay::menu_item ("cm_prev_display_state", "prev_display_state", at, tl::to_string (QObject::tr ("Back<:/back.png>"))));
+    menu_entries.push_back (lay::menu_item ("cm_next_display_state", "next_display_state", at, tl::to_string (QObject::tr ("Forward<:/forward.png>"))));
     menu_entries.push_back (lay::separator ("toolbar_post_navigation_group", at));
   }
 };
diff --git a/src/lay/lay/layMainWindow.h b/src/lay/lay/layMainWindow.h
index 6ffa374e2..b8c8b9b97 100644
--- a/src/lay/lay/layMainWindow.h
+++ b/src/lay/lay/layMainWindow.h
@@ -20,8 +20,6 @@
 
 */
 
-
-
 #ifndef HDR_layMainWindow
 #define HDR_layMainWindow
 
@@ -46,6 +44,7 @@
 #include "layProgress.h"
 #include "layTextProgress.h"
 #include "layTechnology.h"
+#include "layTextProgressDelegate.h"
 #include "tlException.h"
 #include "tlDeferredExecution.h"
 #include "tlObjectCollection.h"
@@ -61,10 +60,6 @@ class QStackedWidget;
 class QDockWidget;
 class QAction;
 
-namespace Ui {
-  class HelpAboutDialog;
-}
-
 namespace lay {
 
 class SettingsForm;
@@ -84,38 +79,19 @@ class Navigator;
 class LayerToolbox;
 class MainWindow;
 class HelpDialog;
+class HelpAboutDialog;
+class ControlWidgetStack;
+class ViewWidgetStack;
+class ProgressWidget;
 
 /**
- *  @brief A dialog for showing the "help about" dialog
+ *  @brief A big main window class
+ *
+ *  The main window is the core UI feature of the application.
+ *  The main window is view container, basic controller, configuration root
+ *  and holder of many resources.
+ *  The main window is a singleton.
  */
-class LAY_PUBLIC HelpAboutDialog
-  : public QDialog
-{
-public:
-  HelpAboutDialog (QWidget *parent); 
-  ~HelpAboutDialog ();
-
-private:
-  Ui::HelpAboutDialog *mp_ui;
-};
-
-class TextProgressDelegate
-  : public lay::TextProgress
-{
-public:
-  TextProgressDelegate (MainWindow *mw, int verbosity);
-
-  virtual void update_progress (tl::Progress *progress);
-  virtual void show_progress_bar (bool show);
-  virtual bool progress_wants_widget () const;
-  virtual void progress_add_widget (QWidget *widget);
-  virtual QWidget *progress_get_widget () const;
-  virtual void progress_remove_widget ();
-
-private:
-  MainWindow *mp_mw;
-};
-
 class LAY_PUBLIC MainWindow
   : public QMainWindow,
     public lay::Dispatcher
@@ -564,17 +540,22 @@ public:
   tl::event<int> view_created_event;
 
   /**
-   *  @brief Add an entry to the MRU list with the initial technology
+   *  @brief Adds an entry to the MRU list with the initial technology
    */
   void add_mru (const std::string &fn);
 
   /**
-   *  @brief Add an entry to the MRU list
+   *  @brief Adds an entry to the MRU list
    */
   void add_mru (const std::string &fn, const std::string &tech);
 
   /**
-   *  @brief Get the technology used for loading or creating layouts
+   *  @brief Adds an entry to a specific MRU list given by the "cfg" configuration option
+   */
+  void add_to_other_mru (const std::string &fn_rel, const std::string &cfg);
+
+  /**
+   *  @brief Gets the technology used for loading or creating layouts
    */
   const std::string &initial_technology () 
   {
@@ -582,7 +563,7 @@ public:
   }
 
   /**
-   *  @brief Set the initial technology used for loading or creating layouts
+   *  @brief Sets the initial technology used for loading or creating layouts
    */
   void set_initial_technology (const std::string &tech)
   {
@@ -637,6 +618,9 @@ public slots:
   void close_current_view ();
   void tab_close_requested (int);
   void open_recent (size_t n);
+  void open_recent_session (size_t n);
+  void open_recent_layer_properties (size_t n);
+  void open_recent_bookmarks (size_t n);
   void view_selected (int index);
   void view_title_changed ();
 
@@ -670,7 +654,7 @@ protected slots:
 protected:
   void update_content ();
   void do_update_menu ();
-  void do_update_file_menu ();
+  void do_update_mru_menus ();
 
 private:
   TextProgressDelegate m_text_progress;
@@ -680,9 +664,9 @@ private:
   QToolBar *mp_tool_bar;
   QDockWidget *mp_navigator_dock_widget;
   lay::Navigator *mp_navigator;
-  QDockWidget *mp_hp_dock_widget, *mp_lp_dock_widget, *mp_libs_dock_widget, *mp_bm_dock_widget;
-  ControlWidgetStack *mp_hp_stack, *mp_lp_stack, *mp_libs_stack, *mp_bm_stack;
-  bool m_hp_visible, m_lp_visible, m_libs_visible, m_bm_visible, m_navigator_visible, m_layer_toolbox_visible;
+  QDockWidget *mp_hp_dock_widget, *mp_lp_dock_widget, *mp_libs_dock_widget, *mp_eo_dock_widget, *mp_bm_dock_widget;
+  ControlWidgetStack *mp_hp_stack, *mp_lp_stack, *mp_libs_stack, *mp_eo_stack, *mp_bm_stack;
+  bool m_hp_visible, m_lp_visible, m_libs_visible, m_eo_visible, m_bm_visible, m_navigator_visible, m_layer_toolbox_visible;
   QDockWidget *mp_layer_toolbox_dock_widget;
   lay::LayerToolbox *mp_layer_toolbox;
   ViewWidgetStack *mp_view_stack;
@@ -700,6 +684,7 @@ private:
   std::vector <lay::LayoutView *> mp_views;
   int m_open_mode;
   std::vector<std::pair<std::string, std::string> > m_mru;
+  std::vector<std::string> m_mru_sessions, m_mru_layer_properties, m_mru_bookmarks;
   QStatusBar *mp_status_bar;
   QStackedWidget *mp_main_stack_widget;
   ProgressWidget *mp_progress_widget;
@@ -712,7 +697,7 @@ private:
   bool m_disable_tab_selected;
   bool m_exited;
   tl::DeferredMethod<MainWindow> dm_do_update_menu;
-  tl::DeferredMethod<MainWindow> dm_do_update_file_menu;
+  tl::DeferredMethod<MainWindow> dm_do_update_mru_menus;
   tl::DeferredMethod<MainWindow> dm_exit;
   QTimer m_message_timer;
   QTimer m_file_changed_timer;
diff --git a/src/lay/lay/layProgressDialog.cc b/src/lay/lay/layProgressDialog.cc
new file mode 100644
index 000000000..5d74fed4f
--- /dev/null
+++ b/src/lay/lay/layProgressDialog.cc
@@ -0,0 +1,75 @@
+
+/*
+
+  KLayout Layout Viewer
+  Copyright (C) 2006-2020 Matthias Koefferlein
+
+  This program is free software; you can redistribute it and/or modify
+  it under the terms of the GNU General Public License as published by
+  the Free Software Foundation; either version 2 of the License, or
+  (at your option) any later version.
+
+  This program is distributed in the hope that it will be useful,
+  but WITHOUT ANY WARRANTY; without even the implied warranty of
+  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+  GNU General Public License for more details.
+
+  You should have received a copy of the GNU General Public License
+  along with this program; if not, write to the Free Software
+  Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
+
+*/
+
+#include "layProgressDialog.h"
+#include "layProgressWidget.h"
+
+#include <QVBoxLayout>
+
+namespace lay
+{
+
+ProgressDialog::ProgressDialog (QWidget *parent, ProgressReporter *pr)
+  : QDialog (parent), mp_pr (pr)
+{
+  QVBoxLayout *vbl = new QVBoxLayout (this);
+  vbl->setMargin (0);
+  vbl->setSpacing (0);
+
+  mp_progress_widget = new ProgressWidget (pr, this, true);
+  mp_progress_widget->setObjectName (QString::fromUtf8 ("progress"));
+  vbl->addWidget (mp_progress_widget);
+
+  setWindowTitle (QObject::tr ("Progress"));
+  setWindowModality (Qt::WindowModal);
+}
+
+void ProgressDialog::closeEvent (QCloseEvent *)
+{
+  if (mp_pr) {
+    //  NOTE: We don't kill on close for now. This creates a too easy way to scrap results.
+    //    mp_pr->signal_break ();
+    //  TODO: there should be a warning saying some jobs are pending.
+  }
+}
+
+void ProgressDialog::set_progress (tl::Progress *progress)
+{
+  mp_progress_widget->set_progress (progress);
+}
+
+void ProgressDialog::add_widget (QWidget *widget)
+{
+  mp_progress_widget->add_widget (widget);
+}
+
+void ProgressDialog::remove_widget ()
+{
+  mp_progress_widget->remove_widget ();
+}
+
+QWidget *ProgressDialog::get_widget () const
+{
+  return mp_progress_widget->get_widget ();
+}
+
+}
diff --git a/src/lay/lay/layProgressDialog.h b/src/lay/lay/layProgressDialog.h
new file mode 100644
index 000000000..f1036fd2d
--- /dev/null
+++ b/src/lay/lay/layProgressDialog.h
@@ -0,0 +1,61 @@
+
+/*
+
+  KLayout Layout Viewer
+  Copyright (C) 2006-2020 Matthias Koefferlein
+
+  This program is free software; you can redistribute it and/or modify
+  it under the terms of the GNU General Public License as published by
+  the Free Software Foundation; either version 2 of the License, or
+  (at your option) any later version.
+
+  This program is distributed in the hope that it will be useful,
+  but WITHOUT ANY WARRANTY; without even the implied warranty of
+  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+  GNU General Public License for more details.
+
+  You should have received a copy of the GNU General Public License
+  along with this program; if not, write to the Free Software
+  Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
+
+*/
+
+
+#ifndef HDR_layProgressDialog
+#define HDR_layProgressDialog
+
+#include "layCommon.h"
+
+#include "tlObject.h"
+#include "tlProgress.h"
+
+#include <QDialog>
+
+namespace lay
+{
+
+class ProgressReporter;
+class ProgressWidget;
+
+class ProgressDialog
+  : public QDialog,
+    public tl::Object
+{
+public:
+  ProgressDialog (QWidget *parent, lay::ProgressReporter *pr);
+
+  void closeEvent (QCloseEvent * /*event*/);
+
+  void set_progress (tl::Progress *progress);
+  void add_widget (QWidget *widget);
+  void remove_widget ();
+  QWidget *get_widget () const;
+
+private:
+  lay::ProgressWidget *mp_progress_widget;
+  lay::ProgressReporter *mp_pr;
+};
+
+}
+
+#endif
diff --git a/src/lay/lay/layResources.qrc b/src/lay/lay/layResources.qrc
index 799f3f325..041ac55e1 100644
--- a/src/lay/lay/layResources.qrc
+++ b/src/lay/lay/layResources.qrc
@@ -127,8 +127,16 @@
         <file alias="folder_12.png">images/folder_12.png</file>
         <file alias="file_12.png">images/file_12.png</file>
         <file alias="empty_12.png">images/empty_12.png</file>
+        <file alias="fit_front.png">images/fit_front.png</file>
+        <file alias="fit_back.png">images/fit_back.png</file>
+        <file alias="fit_left.png">images/fit_left.png</file>
+        <file alias="fit_right.png">images/fit_right.png</file>
+        <file alias="fit_top.png">images/fit_top.png</file>
+        <file alias="fit_bottom.png">images/fit_bottom.png</file>
         <file alias="unlocked_16.png">images/unlocked_16.png</file>
         <file alias="locked_16.png">images/locked_16.png</file>
+        <file alias="bookmark.png">images/bookmark.png</file>
+        <file alias="bookmark_16.png">images/bookmark_16.png</file>
     </qresource>
     <qresource prefix="/syntax">
         <file alias="ruby.xml">syntax/ruby.xml</file>
diff --git a/src/lay/lay/laySignalHandler.cc b/src/lay/lay/laySignalHandler.cc
index f1d7462a0..73da25731 100644
--- a/src/lay/lay/laySignalHandler.cc
+++ b/src/lay/lay/laySignalHandler.cc
@@ -450,7 +450,7 @@ void install_signal_handlers ()
   act.sa_sigaction = signal_handler;
   sigemptyset (&act.sa_mask);
   act.sa_flags = SA_SIGINFO;
-#if !defined(__APPLE__) && !defined(__OpenBSD__)
+#if !defined(__APPLE__) && !defined(__FreeBSD__) && !defined(__OpenBSD__)
   act.sa_restorer = 0;
 #endif
 
diff --git a/src/lay/lay/layTextProgressDelegate.cc b/src/lay/lay/layTextProgressDelegate.cc
new file mode 100644
index 000000000..d0dd0db2f
--- /dev/null
+++ b/src/lay/lay/layTextProgressDelegate.cc
@@ -0,0 +1,73 @@
+
+/*
+
+  KLayout Layout Viewer
+  Copyright (C) 2006-2020 Matthias Koefferlein
+
+  This program is free software; you can redistribute it and/or modify
+  it under the terms of the GNU General Public License as published by
+  the Free Software Foundation; either version 2 of the License, or
+  (at your option) any later version.
+
+  This program is distributed in the hope that it will be useful,
+  but WITHOUT ANY WARRANTY; without even the implied warranty of
+  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+  GNU General Public License for more details.
+
+  You should have received a copy of the GNU General Public License
+  along with this program; if not, write to the Free Software
+  Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
+
+*/
+
+#include "layTextProgressDelegate.h"
+#include "layMainWindow.h"
+
+namespace lay
+{
+
+TextProgressDelegate::TextProgressDelegate (MainWindow *mw, int verbosity)
+  : lay::TextProgress (verbosity), mp_mw (mw)
+{
+  //  .. nothing yet ..
+}
+
+void TextProgressDelegate::update_progress (tl::Progress *progress)
+{
+  if (!mp_mw->update_progress (progress)) {
+    lay::TextProgress::update_progress (progress);
+  }
+}
+
+void TextProgressDelegate::show_progress_bar (bool show)
+{
+  if (!mp_mw->show_progress_bar (show)) {
+    lay::TextProgress::show_progress_bar (show);
+  }
+}
+
+bool TextProgressDelegate::progress_wants_widget () const
+{
+  return mp_mw != 0 && mp_mw->progress_wants_widget ();
+}
+
+void TextProgressDelegate::progress_add_widget (QWidget *widget)
+{
+  if (mp_mw) {
+    mp_mw->progress_add_widget (widget);
+  }
+}
+
+QWidget *TextProgressDelegate::progress_get_widget () const
+{
+  return mp_mw ? mp_mw->progress_get_widget () : 0;
+}
+
+void TextProgressDelegate::progress_remove_widget ()
+{
+  if (mp_mw) {
+    mp_mw->progress_remove_widget ();
+  }
+}
+
+}
diff --git a/src/lay/lay/layTextProgressDelegate.h b/src/lay/lay/layTextProgressDelegate.h
new file mode 100644
index 000000000..d45128861
--- /dev/null
+++ b/src/lay/lay/layTextProgressDelegate.h
@@ -0,0 +1,55 @@
+
+/*
+
+  KLayout Layout Viewer
+  Copyright (C) 2006-2020 Matthias Koefferlein
+
+  This program is free software; you can redistribute it and/or modify
+  it under the terms of the GNU General Public License as published by
+  the Free Software Foundation; either version 2 of the License, or
+  (at your option) any later version.
+
+  This program is distributed in the hope that it will be useful,
+  but WITHOUT ANY WARRANTY; without even the implied warranty of
+  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+  GNU General Public License for more details.
+
+  You should have received a copy of the GNU General Public License
+  along with this program; if not, write to the Free Software
+  Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
+
+*/
+
+
+#ifndef HDR_layTextProgressDelegate
+#define HDR_layTextProgressDelegate
+
+#include "layCommon.h"
+
+#include "layTextProgress.h"
+
+namespace lay
+{
+
+class MainWindow;
+
+class TextProgressDelegate
+  : public lay::TextProgress
+{
+public:
+  TextProgressDelegate (MainWindow *mw, int verbosity);
+
+  virtual void update_progress (tl::Progress *progress);
+  virtual void show_progress_bar (bool show);
+  virtual bool progress_wants_widget () const;
+  virtual void progress_add_widget (QWidget *widget);
+  virtual QWidget *progress_get_widget () const;
+  virtual void progress_remove_widget ();
+
+private:
+  MainWindow *mp_mw;
+};
+
+}
+
+#endif
diff --git a/src/lay/lay/layViewWidgetStack.cc b/src/lay/lay/layViewWidgetStack.cc
new file mode 100644
index 000000000..7d7b51f81
--- /dev/null
+++ b/src/lay/lay/layViewWidgetStack.cc
@@ -0,0 +1,103 @@
+
+/*
+
+  KLayout Layout Viewer
+  Copyright (C) 2006-2020 Matthias Koefferlein
+
+  This program is free software; you can redistribute it and/or modify
+  it under the terms of the GNU General Public License as published by
+  the Free Software Foundation; either version 2 of the License, or
+  (at your option) any later version.
+
+  This program is distributed in the hope that it will be useful,
+  but WITHOUT ANY WARRANTY; without even the implied warranty of
+  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+  GNU General Public License for more details.
+
+  You should have received a copy of the GNU General Public License
+  along with this program; if not, write to the Free Software
+  Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
+
+*/
+
+#include "layViewWidgetStack.h"
+#include "layLayoutView.h"
+
+#include <QLabel>
+
+namespace lay
+{
+
+ViewWidgetStack::ViewWidgetStack (QWidget *parent, const char *name)
+  : QWidget (parent)
+{
+  setObjectName (QString::fromUtf8 (name));
+
+  mp_bglabel = new QLabel (this);
+  mp_bglabel->setAutoFillBackground (true);
+  mp_bglabel->setText (QObject::tr ("<html><body><p><img src=\":/logo.png\"/></p><p>Use File/Open to open a layout</p></body></html>"));
+  mp_bglabel->setAlignment (Qt::AlignVCenter | Qt::AlignHCenter);
+  mp_bglabel->show ();
+}
+
+void ViewWidgetStack::add_widget (LayoutView *w)
+{
+  m_widgets.push_back (w);
+  w->setParent (this);
+  resize_children ();
+  raise_widget (m_widgets.size () - 1);
+
+  updateGeometry ();
+}
+
+void ViewWidgetStack::remove_widget (size_t index)
+{
+  if (index < m_widgets.size ()) {
+    m_widgets.erase (m_widgets.begin () + index);
+  }
+  if (m_widgets.size () == 0) {
+    mp_bglabel->show ();
+  }
+}
+
+void ViewWidgetStack::raise_widget (size_t index)
+{
+  if (index < m_widgets.size ()) {
+    mp_bglabel->hide ();
+    m_widgets [index]->show ();
+  } else {
+    mp_bglabel->show ();
+  }
+
+  size_t i = 0;
+  for (std::vector <LayoutView *>::iterator child = m_widgets.begin (); child != m_widgets.end (); ++child, ++i) {
+    if (i != index) {
+      (*child)->hide ();
+    }
+  }
+}
+
+LayoutView *ViewWidgetStack::widget (size_t index)
+{
+  if (index < m_widgets.size ()) {
+    return m_widgets [index];
+  } else {
+    return 0;
+  }
+}
+
+QWidget *ViewWidgetStack::background_widget ()
+{
+  return mp_bglabel;
+}
+
+void ViewWidgetStack::resize_children ()
+{
+  //  set the geometry of all children
+  for (std::vector <LayoutView *>::iterator child = m_widgets.begin (); child != m_widgets.end (); ++child) {
+    (*child)->setGeometry (0, 0, width (), height ());
+  }
+  mp_bglabel->setGeometry (0, 0, width (), height ());
+}
+
+}
diff --git a/src/lay/lay/layViewWidgetStack.h b/src/lay/lay/layViewWidgetStack.h
new file mode 100644
index 000000000..c4e7b1c1e
--- /dev/null
+++ b/src/lay/lay/layViewWidgetStack.h
@@ -0,0 +1,64 @@
+
+/*
+
+  KLayout Layout Viewer
+  Copyright (C) 2006-2020 Matthias Koefferlein
+
+  This program is free software; you can redistribute it and/or modify
+  it under the terms of the GNU General Public License as published by
+  the Free Software Foundation; either version 2 of the License, or
+  (at your option) any later version.
+
+  This program is distributed in the hope that it will be useful,
+  but WITHOUT ANY WARRANTY; without even the implied warranty of
+  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+  GNU General Public License for more details.
+
+  You should have received a copy of the GNU General Public License
+  along with this program; if not, write to the Free Software
+  Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
+
+*/
+
+
+#ifndef HDR_layViewWidgetStack
+#define HDR_layViewWidgetStack
+
+#include "layCommon.h"
+
+#include <QWidget>
+
+class QLabel;
+
+namespace lay
+{
+
+class LayoutView;
+
+class ViewWidgetStack
+  : public QWidget
+{
+public:
+  ViewWidgetStack (QWidget *parent = 0, const char *name = 0);
+
+  void add_widget (LayoutView *w);
+  void remove_widget (size_t index);
+  void raise_widget (size_t index);
+  LayoutView *widget (size_t index);
+  QWidget *background_widget ();
+
+protected:
+  virtual void resizeEvent (QResizeEvent *)
+  {
+    resize_children ();
+  }
+
+  void resize_children ();
+
+  std::vector <LayoutView *> m_widgets;
+  QLabel *mp_bglabel;
+};
+
+}
+
+#endif
diff --git a/src/laybasic/laybasic/BrowserPanel.ui b/src/laybasic/laybasic/BrowserPanel.ui
index af94c7c61..d77c6c45a 100644
--- a/src/laybasic/laybasic/BrowserPanel.ui
+++ b/src/laybasic/laybasic/BrowserPanel.ui
@@ -29,7 +29,7 @@
    <property name="spacing">
     <number>2</number>
    </property>
-   <item row="0" column="1">
+   <item row="0" column="5">
     <spacer>
      <property name="orientation">
       <enum>Qt::Horizontal</enum>
@@ -45,30 +45,7 @@
      </property>
     </spacer>
    </item>
-   <item row="0" column="7">
-    <widget class="QToolButton" name="next_topic_pb">
-     <property name="toolTip">
-      <string>Next Topic</string>
-     </property>
-     <property name="text">
-      <string>...</string>
-     </property>
-     <property name="icon">
-      <iconset resource="../../lay/lay/layResources.qrc">
-       <normaloff>:/next_topic.png</normaloff>:/next_topic.png</iconset>
-     </property>
-     <property name="iconSize">
-      <size>
-       <width>24</width>
-       <height>24</height>
-      </size>
-     </property>
-     <property name="autoRaise">
-      <bool>true</bool>
-     </property>
-    </widget>
-   </item>
-   <item row="1" column="0" colspan="10">
+   <item row="1" column="0" colspan="14">
     <widget class="QFrame" name="frame">
      <property name="minimumSize">
       <size>
@@ -77,7 +54,7 @@
       </size>
      </property>
      <property name="frameShape">
-      <enum>QFrame::StyledPanel</enum>
+      <enum>QFrame::NoFrame</enum>
      </property>
      <property name="frameShadow">
       <enum>QFrame::Raised</enum>
@@ -100,54 +77,211 @@
         <property name="orientation">
          <enum>Qt::Horizontal</enum>
         </property>
-        <widget class="QTreeWidget" name="outline_tree">
+        <widget class="QFrame" name="frame_2">
          <property name="sizePolicy">
-          <sizepolicy hsizetype="Preferred" vsizetype="Expanding">
+          <sizepolicy hsizetype="Preferred" vsizetype="Preferred">
            <horstretch>0</horstretch>
            <verstretch>0</verstretch>
           </sizepolicy>
          </property>
-         <property name="baseSize">
-          <size>
-           <width>0</width>
-           <height>0</height>
-          </size>
+         <property name="frameShape">
+          <enum>QFrame::NoFrame</enum>
          </property>
-         <property name="rootIsDecorated">
-          <bool>false</bool>
+         <property name="frameShadow">
+          <enum>QFrame::Raised</enum>
          </property>
-         <property name="itemsExpandable">
-          <bool>true</bool>
-         </property>
-         <property name="expandsOnDoubleClick">
-          <bool>false</bool>
-         </property>
-         <column>
-          <property name="text">
-           <string notr="true">1</string>
+         <layout class="QVBoxLayout" name="verticalLayout_3">
+          <property name="leftMargin">
+           <number>0</number>
           </property>
-         </column>
+          <property name="topMargin">
+           <number>0</number>
+          </property>
+          <property name="rightMargin">
+           <number>0</number>
+          </property>
+          <property name="bottomMargin">
+           <number>0</number>
+          </property>
+          <item>
+           <widget class="QSplitter" name="splitter_2">
+            <property name="orientation">
+             <enum>Qt::Vertical</enum>
+            </property>
+            <widget class="QTreeWidget" name="outline_tree">
+             <property name="sizePolicy">
+              <sizepolicy hsizetype="Preferred" vsizetype="Expanding">
+               <horstretch>0</horstretch>
+               <verstretch>0</verstretch>
+              </sizepolicy>
+             </property>
+             <property name="baseSize">
+              <size>
+               <width>0</width>
+               <height>0</height>
+              </size>
+             </property>
+             <property name="rootIsDecorated">
+              <bool>false</bool>
+             </property>
+             <property name="itemsExpandable">
+              <bool>true</bool>
+             </property>
+             <property name="expandsOnDoubleClick">
+              <bool>false</bool>
+             </property>
+             <column>
+              <property name="text">
+               <string notr="true">1</string>
+              </property>
+             </column>
+            </widget>
+            <widget class="QTreeWidget" name="browser_bookmark_view">
+             <property name="rootIsDecorated">
+              <bool>false</bool>
+             </property>
+             <column>
+              <property name="text">
+               <string>Favorites</string>
+              </property>
+             </column>
+            </widget>
+           </widget>
+          </item>
+         </layout>
         </widget>
-        <widget class="lay::BrowserTextWidget" name="browser">
+        <widget class="QFrame" name="frame_3">
          <property name="sizePolicy">
-          <sizepolicy hsizetype="Preferred" vsizetype="Expanding">
-           <horstretch>4</horstretch>
+          <sizepolicy hsizetype="Preferred" vsizetype="Preferred">
+           <horstretch>1</horstretch>
            <verstretch>0</verstretch>
           </sizepolicy>
          </property>
+         <property name="frameShape">
+          <enum>QFrame::NoFrame</enum>
+         </property>
+         <property name="frameShadow">
+          <enum>QFrame::Raised</enum>
+         </property>
+         <layout class="QVBoxLayout" name="verticalLayout_2">
+          <property name="leftMargin">
+           <number>0</number>
+          </property>
+          <property name="topMargin">
+           <number>0</number>
+          </property>
+          <property name="rightMargin">
+           <number>0</number>
+          </property>
+          <property name="bottomMargin">
+           <number>0</number>
+          </property>
+          <item>
+           <widget class="lay::BrowserTextWidget" name="browser">
+            <property name="sizePolicy">
+             <sizepolicy hsizetype="Preferred" vsizetype="Expanding">
+              <horstretch>0</horstretch>
+              <verstretch>0</verstretch>
+             </sizepolicy>
+            </property>
+           </widget>
+          </item>
+          <item>
+           <widget class="QFrame" name="search_frame">
+            <property name="frameShape">
+             <enum>QFrame::NoFrame</enum>
+            </property>
+            <property name="frameShadow">
+             <enum>QFrame::Raised</enum>
+            </property>
+            <layout class="QHBoxLayout" name="horizontalLayout">
+             <property name="spacing">
+              <number>2</number>
+             </property>
+             <property name="leftMargin">
+              <number>0</number>
+             </property>
+             <property name="topMargin">
+              <number>0</number>
+             </property>
+             <property name="rightMargin">
+              <number>0</number>
+             </property>
+             <property name="bottomMargin">
+              <number>0</number>
+             </property>
+             <item>
+              <widget class="QLabel" name="label_3">
+               <property name="text">
+                <string>  Find on page  </string>
+               </property>
+              </widget>
+             </item>
+             <item>
+              <widget class="QToolButton" name="on_page_search_next">
+               <property name="text">
+                <string>...</string>
+               </property>
+               <property name="icon">
+                <iconset resource="../../lay/lay/layResources.qrc">
+                 <normaloff>:/find.png</normaloff>:/find.png</iconset>
+               </property>
+               <property name="autoRaise">
+                <bool>true</bool>
+               </property>
+              </widget>
+             </item>
+             <item>
+              <widget class="QLineEdit" name="on_page_search_edit">
+               <property name="clearButtonEnabled">
+                <bool>true</bool>
+               </property>
+              </widget>
+             </item>
+             <item>
+              <widget class="QToolButton" name="search_close_button">
+               <property name="text">
+                <string>...</string>
+               </property>
+               <property name="icon">
+                <iconset resource="../../lay/lay/layResources.qrc">
+                 <normaloff>:/clear_edit.png</normaloff>:/clear_edit.png</iconset>
+               </property>
+               <property name="autoRaise">
+                <bool>true</bool>
+               </property>
+              </widget>
+             </item>
+            </layout>
+           </widget>
+          </item>
+         </layout>
         </widget>
        </widget>
       </item>
      </layout>
     </widget>
    </item>
-   <item row="0" column="9">
-    <widget class="QLineEdit" name="searchEdit">
-     <property name="sizePolicy">
-      <sizepolicy hsizetype="Expanding" vsizetype="Fixed">
-       <horstretch>0</horstretch>
-       <verstretch>0</verstretch>
-      </sizepolicy>
+   <item row="0" column="3">
+    <widget class="QToolButton" name="forward_pb">
+     <property name="toolTip">
+      <string>Forward</string>
+     </property>
+     <property name="text">
+      <string>...</string>
+     </property>
+     <property name="icon">
+      <iconset resource="../../lay/lay/layResources.qrc">
+       <normaloff>:/forward.png</normaloff>:/forward.png</iconset>
+     </property>
+     <property name="iconSize">
+      <size>
+       <width>24</width>
+       <height>24</height>
+      </size>
+     </property>
+     <property name="autoRaise">
+      <bool>true</bool>
      </property>
     </widget>
    </item>
@@ -197,6 +331,22 @@
      </property>
     </widget>
    </item>
+   <item row="0" column="1">
+    <spacer>
+     <property name="orientation">
+      <enum>Qt::Horizontal</enum>
+     </property>
+     <property name="sizeType">
+      <enum>QSizePolicy::Fixed</enum>
+     </property>
+     <property name="sizeHint" stdset="0">
+      <size>
+       <width>6</width>
+       <height>20</height>
+      </size>
+     </property>
+    </spacer>
+   </item>
    <item row="0" column="6">
     <widget class="QToolButton" name="prev_topic_pb">
      <property name="toolTip">
@@ -220,17 +370,47 @@
      </property>
     </widget>
    </item>
-   <item row="0" column="3">
-    <widget class="QToolButton" name="forward_pb">
+   <item row="0" column="8">
+    <spacer name="horizontalSpacer">
+     <property name="orientation">
+      <enum>Qt::Horizontal</enum>
+     </property>
+     <property name="sizeType">
+      <enum>QSizePolicy::Fixed</enum>
+     </property>
+     <property name="sizeHint" stdset="0">
+      <size>
+       <width>10</width>
+       <height>20</height>
+      </size>
+     </property>
+    </spacer>
+   </item>
+   <item row="0" column="11">
+    <widget class="QToolButton" name="search_button">
+     <property name="text">
+      <string>...</string>
+     </property>
+     <property name="icon">
+      <iconset resource="../../lay/lay/layResources.qrc">
+       <normaloff>:/find.png</normaloff>:/find.png</iconset>
+     </property>
+     <property name="autoRaise">
+      <bool>true</bool>
+     </property>
+    </widget>
+   </item>
+   <item row="0" column="7">
+    <widget class="QToolButton" name="next_topic_pb">
      <property name="toolTip">
-      <string>Forward</string>
+      <string>Next Topic</string>
      </property>
      <property name="text">
       <string>...</string>
      </property>
      <property name="icon">
       <iconset resource="../../lay/lay/layResources.qrc">
-       <normaloff>:/forward.png</normaloff>:/forward.png</iconset>
+       <normaloff>:/next_topic.png</normaloff>:/next_topic.png</iconset>
      </property>
      <property name="iconSize">
       <size>
@@ -243,7 +423,20 @@
      </property>
     </widget>
    </item>
-   <item row="0" column="8">
+   <item row="0" column="12">
+    <widget class="QLineEdit" name="search_edit">
+     <property name="sizePolicy">
+      <sizepolicy hsizetype="Expanding" vsizetype="Fixed">
+       <horstretch>0</horstretch>
+       <verstretch>0</verstretch>
+      </sizepolicy>
+     </property>
+     <property name="clearButtonEnabled">
+      <bool>true</bool>
+     </property>
+    </widget>
+   </item>
+   <item row="0" column="10">
     <spacer>
      <property name="orientation">
       <enum>Qt::Horizontal</enum>
@@ -266,23 +459,51 @@
      </property>
     </widget>
    </item>
-   <item row="0" column="5">
-    <spacer>
-     <property name="orientation">
-      <enum>Qt::Horizontal</enum>
+   <item row="0" column="9">
+    <widget class="QToolButton" name="bookmark_pb">
+     <property name="toolTip">
+      <string>Add this location to the favorites list</string>
      </property>
-     <property name="sizeType">
-      <enum>QSizePolicy::Fixed</enum>
+     <property name="text">
+      <string>...</string>
      </property>
-     <property name="sizeHint" stdset="0">
+     <property name="icon">
+      <iconset resource="../../lay/lay/layResources.qrc">
+       <normaloff>:/bookmark.png</normaloff>:/bookmark.png</iconset>
+     </property>
+     <property name="iconSize">
       <size>
-       <width>6</width>
-       <height>20</height>
+       <width>24</width>
+       <height>24</height>
       </size>
      </property>
-    </spacer>
+     <property name="autoRaise">
+      <bool>true</bool>
+     </property>
+    </widget>
    </item>
   </layout>
+  <action name="action_find">
+   <property name="text">
+    <string>Find</string>
+   </property>
+   <property name="shortcut">
+    <string>Ctrl+F</string>
+   </property>
+  </action>
+  <action name="action_bookmark">
+   <property name="text">
+    <string>Bookmark</string>
+   </property>
+   <property name="shortcut">
+    <string>Ctrl+B</string>
+   </property>
+  </action>
+  <action name="action_delete_bookmark">
+   <property name="text">
+    <string>Delete Entry</string>
+   </property>
+  </action>
  </widget>
  <customwidgets>
   <customwidget>
@@ -292,7 +513,7 @@
   </customwidget>
  </customwidgets>
  <tabstops>
-  <tabstop>searchEdit</tabstop>
+  <tabstop>search_edit</tabstop>
   <tabstop>back_pb</tabstop>
   <tabstop>forward_pb</tabstop>
   <tabstop>home_pb</tabstop>
@@ -300,5 +521,22 @@
  <resources>
   <include location="../../lay/lay/layResources.qrc"/>
  </resources>
- <connections/>
+ <connections>
+  <connection>
+   <sender>search_close_button</sender>
+   <signal>clicked()</signal>
+   <receiver>search_frame</receiver>
+   <slot>hide()</slot>
+   <hints>
+    <hint type="sourcelabel">
+     <x>816</x>
+     <y>571</y>
+    </hint>
+    <hint type="destinationlabel">
+     <x>371</x>
+     <y>577</y>
+    </hint>
+   </hints>
+  </connection>
+ </connections>
 </ui>
diff --git a/src/laybasic/laybasic/D25TechnologyComponentEditor.ui b/src/laybasic/laybasic/D25TechnologyComponentEditor.ui
new file mode 100644
index 000000000..b1901ba63
--- /dev/null
+++ b/src/laybasic/laybasic/D25TechnologyComponentEditor.ui
@@ -0,0 +1,54 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<ui version="4.0">
+ <class>D25TechnologyComponentEditor</class>
+ <widget class="QFrame" name="D25TechnologyComponentEditor">
+  <property name="geometry">
+   <rect>
+    <x>0</x>
+    <y>0</y>
+    <width>549</width>
+    <height>434</height>
+   </rect>
+  </property>
+  <property name="windowTitle">
+   <string>Settings</string>
+  </property>
+  <layout class="QGridLayout" name="gridLayout">
+   <item row="0" column="0">
+    <widget class="QLabel" name="label">
+     <property name="text">
+      <string>2.5d Vertical Stack Information</string>
+     </property>
+    </widget>
+   </item>
+   <item row="0" column="1">
+    <widget class="QLabel" name="lnum_label">
+     <property name="sizePolicy">
+      <sizepolicy hsizetype="Fixed" vsizetype="Preferred">
+       <horstretch>0</horstretch>
+       <verstretch>0</verstretch>
+      </sizepolicy>
+     </property>
+     <property name="text">
+      <string>Line</string>
+     </property>
+     <property name="alignment">
+      <set>Qt::AlignRight|Qt::AlignTrailing|Qt::AlignVCenter</set>
+     </property>
+    </widget>
+   </item>
+   <item row="1" column="0" colspan="2">
+    <widget class="QTextEdit" name="src_te">
+     <property name="font">
+      <font>
+       <family>Monospace</family>
+      </font>
+     </property>
+    </widget>
+   </item>
+  </layout>
+ </widget>
+ <layoutdefault spacing="6" margin="11"/>
+ <resources/>
+ <connections/>
+</ui>
diff --git a/src/laybasic/laybasic/LayoutViewConfigPage2d.ui b/src/laybasic/laybasic/LayoutViewConfigPage2d.ui
new file mode 100644
index 000000000..0a9fc17f5
--- /dev/null
+++ b/src/laybasic/laybasic/LayoutViewConfigPage2d.ui
@@ -0,0 +1,151 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<ui version="4.0">
+ <class>LayoutViewConfigPage2d</class>
+ <widget class="QFrame" name="LayoutViewConfigPage2d">
+  <property name="geometry">
+   <rect>
+    <x>0</x>
+    <y>0</y>
+    <width>608</width>
+    <height>318</height>
+   </rect>
+  </property>
+  <property name="windowTitle">
+   <string>Settings</string>
+  </property>
+  <layout class="QVBoxLayout">
+   <property name="spacing">
+    <number>6</number>
+   </property>
+   <property name="leftMargin">
+    <number>9</number>
+   </property>
+   <property name="topMargin">
+    <number>9</number>
+   </property>
+   <property name="rightMargin">
+    <number>9</number>
+   </property>
+   <property name="bottomMargin">
+    <number>9</number>
+   </property>
+   <item>
+    <widget class="QGroupBox" name="tracking_cb">
+     <property name="title">
+      <string>Mouse tracking</string>
+     </property>
+     <property name="checkable">
+      <bool>true</bool>
+     </property>
+     <layout class="QGridLayout">
+      <property name="leftMargin">
+       <number>9</number>
+      </property>
+      <property name="topMargin">
+       <number>9</number>
+      </property>
+      <property name="rightMargin">
+       <number>9</number>
+      </property>
+      <property name="bottomMargin">
+       <number>9</number>
+      </property>
+      <property name="spacing">
+       <number>6</number>
+      </property>
+      <item row="1" column="1">
+       <widget class="lay::ColorButton" name="color_pb">
+        <property name="toolTip">
+         <string>The color in which the rulers are drawn</string>
+        </property>
+        <property name="text">
+         <string/>
+        </property>
+       </widget>
+      </item>
+      <item row="1" column="2">
+       <spacer>
+        <property name="orientation">
+         <enum>Qt::Horizontal</enum>
+        </property>
+        <property name="sizeHint" stdset="0">
+         <size>
+          <width>71</width>
+          <height>31</height>
+         </size>
+        </property>
+       </spacer>
+      </item>
+      <item row="1" column="0">
+       <widget class="QLabel" name="textLabel3_2">
+        <property name="text">
+         <string>Cursor color</string>
+        </property>
+       </widget>
+      </item>
+      <item row="0" column="0" colspan="3">
+       <widget class="QLabel" name="label">
+        <property name="text">
+         <string>With mouse tracking enabled, a cursor will appear which indicates the snapped mouse position and whether the mouse snaps to objects.</string>
+        </property>
+        <property name="wordWrap">
+         <bool>true</bool>
+        </property>
+       </widget>
+      </item>
+     </layout>
+    </widget>
+   </item>
+   <item>
+    <widget class="QFrame" name="frame">
+     <property name="frameShape">
+      <enum>QFrame::NoFrame</enum>
+     </property>
+     <property name="frameShadow">
+      <enum>QFrame::Raised</enum>
+     </property>
+     <layout class="QHBoxLayout" name="horizontalLayout">
+      <property name="leftMargin">
+       <number>0</number>
+      </property>
+      <property name="topMargin">
+       <number>0</number>
+      </property>
+      <property name="rightMargin">
+       <number>0</number>
+      </property>
+      <property name="bottomMargin">
+       <number>0</number>
+      </property>
+     </layout>
+    </widget>
+   </item>
+   <item>
+    <spacer name="verticalSpacer_2">
+     <property name="orientation">
+      <enum>Qt::Vertical</enum>
+     </property>
+     <property name="sizeHint" stdset="0">
+      <size>
+       <width>20</width>
+       <height>40</height>
+      </size>
+     </property>
+    </spacer>
+   </item>
+  </layout>
+ </widget>
+ <layoutdefault spacing="6" margin="11"/>
+ <customwidgets>
+  <customwidget>
+   <class>lay::ColorButton</class>
+   <extends>QPushButton</extends>
+   <header>layWidgets.h</header>
+  </customwidget>
+ </customwidgets>
+ <tabstops>
+  <tabstop>color_pb</tabstop>
+ </tabstops>
+ <resources/>
+ <connections/>
+</ui>
diff --git a/src/laybasic/laybasic/PropertiesDialog.ui b/src/laybasic/laybasic/PropertiesDialog.ui
index dc1e57646..4edb7171e 100644
--- a/src/laybasic/laybasic/PropertiesDialog.ui
+++ b/src/laybasic/laybasic/PropertiesDialog.ui
@@ -17,7 +17,16 @@
    <property name="spacing">
     <number>6</number>
    </property>
-   <property name="margin">
+   <property name="leftMargin">
+    <number>9</number>
+   </property>
+   <property name="topMargin">
+    <number>9</number>
+   </property>
+   <property name="rightMargin">
+    <number>9</number>
+   </property>
+   <property name="bottomMargin">
     <number>9</number>
    </property>
    <item>
@@ -54,7 +63,16 @@
       <property name="spacing">
        <number>6</number>
       </property>
-      <property name="margin">
+      <property name="leftMargin">
+       <number>0</number>
+      </property>
+      <property name="topMargin">
+       <number>0</number>
+      </property>
+      <property name="rightMargin">
+       <number>0</number>
+      </property>
+      <property name="bottomMargin">
        <number>0</number>
       </property>
       <item>
@@ -69,7 +87,7 @@
          <string>Previous</string>
         </property>
         <property name="icon">
-         <iconset resource="layResources.qrc">
+         <iconset resource="../../lay/lay/layResources.qrc">
           <normaloff>:/left.png</normaloff>:/left.png</iconset>
         </property>
         <property name="default">
@@ -89,7 +107,7 @@
          <string>Next</string>
         </property>
         <property name="icon">
-         <iconset resource="layResources.qrc">
+         <iconset resource="../../lay/lay/layResources.qrc">
           <normaloff>:/right.png</normaloff>:/right.png</iconset>
         </property>
         <property name="default">
@@ -97,6 +115,39 @@
         </property>
        </widget>
       </item>
+      <item>
+       <spacer name="horizontalSpacer">
+        <property name="orientation">
+         <enum>Qt::Horizontal</enum>
+        </property>
+        <property name="sizeType">
+         <enum>QSizePolicy::Fixed</enum>
+        </property>
+        <property name="sizeHint" stdset="0">
+         <size>
+          <width>10</width>
+          <height>20</height>
+         </size>
+        </property>
+       </spacer>
+      </item>
+      <item>
+       <widget class="QCheckBox" name="apply_to_all_cbx">
+        <property name="text">
+         <string>Change all</string>
+        </property>
+       </widget>
+      </item>
+      <item>
+       <widget class="QCheckBox" name="relative_cbx">
+        <property name="enabled">
+         <bool>false</bool>
+        </property>
+        <property name="text">
+         <string>Relative</string>
+        </property>
+       </widget>
+      </item>
       <item>
        <spacer>
         <property name="orientation">
@@ -120,20 +171,6 @@
         </property>
        </widget>
       </item>
-      <item>
-       <widget class="QPushButton" name="apply_button">
-        <property name="text">
-         <string>Apply</string>
-        </property>
-       </widget>
-      </item>
-      <item>
-       <widget class="QPushButton" name="apply_to_all_button">
-        <property name="text">
-         <string>Apply To All</string>
-        </property>
-       </widget>
-      </item>
       <item>
        <widget class="QPushButton" name="cancel_button">
         <property name="text">
@@ -148,7 +185,24 @@
  </widget>
  <layoutdefault spacing="6" margin="11"/>
  <resources>
-  <include location="layResources.qrc"/>
+  <include location="../../lay/lay/layResources.qrc"/>
  </resources>
- <connections/>
+ <connections>
+  <connection>
+   <sender>apply_to_all_cbx</sender>
+   <signal>toggled(bool)</signal>
+   <receiver>relative_cbx</receiver>
+   <slot>setEnabled(bool)</slot>
+   <hints>
+    <hint type="sourcelabel">
+     <x>260</x>
+     <y>372</y>
+    </hint>
+    <hint type="destinationlabel">
+     <x>320</x>
+     <y>372</y>
+    </hint>
+   </hints>
+  </connection>
+ </connections>
 </ui>
diff --git a/src/laybasic/laybasic/gsiDeclLayLayoutView.cc b/src/laybasic/laybasic/gsiDeclLayLayoutView.cc
index eae19ef72..a2f1d7cb7 100644
--- a/src/laybasic/laybasic/gsiDeclLayLayoutView.cc
+++ b/src/laybasic/laybasic/gsiDeclLayLayoutView.cc
@@ -467,6 +467,12 @@ Class<lay::LayoutView> decl_LayoutView (QT_EXTERNAL_BASE (QWidget) "lay", "Layou
     "\n"
     "This constant has been introduced in version 0.27.\n"
   ) +
+  gsi::constant ("LV_NoEditorOptionsPanel", (unsigned int) lay::LayoutView::LV_NoEditorOptionsPanel,
+    "@brief With this option, no editor options panel will be provided (see \\editor_options_frame)\n"
+    "Use this value with the constructor's 'options' argument.\n"
+    "\n"
+    "This constant has been introduced in version 0.27.\n"
+  ) +
   gsi::constant ("LV_NoBookmarksView", (unsigned int) lay::LayoutView::LV_NoBookmarksView,
     "@brief With this option, no bookmarks view will be provided (see \\bookmarks_frame)\n"
     "Use this value with the constructor's 'options' argument.\n"
diff --git a/src/laybasic/laybasic/layAbstractMenu.cc b/src/laybasic/laybasic/layAbstractMenu.cc
index df59ab6ce..bf557a699 100644
--- a/src/laybasic/laybasic/layAbstractMenu.cc
+++ b/src/laybasic/laybasic/layAbstractMenu.cc
@@ -963,6 +963,26 @@ AbstractMenu::build_detached (const std::string &name, QFrame *mbar)
   menu_layout->addStretch (1);
 }
 
+static QAction *insert_action_after (QWidget *widget, QAction *after, QAction *action)
+{
+  QList<QAction *> actions = widget->actions ();
+
+  QAction *before = 0;
+  if (after == 0) {
+    if (! actions.isEmpty ()) {
+      before = actions.front ();
+    }
+  } else {
+    int index = actions.indexOf (after);
+    if (index >= 0 && index + 1 < actions.size ()) {
+      before = actions [index + 1];
+    }
+  }
+  widget->insertAction (before, action);
+
+  return action;
+}
+
 void
 AbstractMenu::build (QMenuBar *mbar, QToolBar *tbar)
 {
@@ -979,6 +999,8 @@ AbstractMenu::build (QMenuBar *mbar, QToolBar *tbar)
     }
   }
 
+  QAction *prev_action = 0;
+
   for (std::list<AbstractMenuItem>::iterator c = m_root.children.begin (); c != m_root.children.end (); ++c) {
 
     if (c->has_submenu ()) {
@@ -1015,19 +1037,20 @@ AbstractMenu::build (QMenuBar *mbar, QToolBar *tbar)
         if (c->menu () == 0) {
           QMenu *menu = new QMenu (mp_dispatcher->menu_parent_widget ());
           menu->setTitle (tl::to_qstring (c->action ()->get_title ()));
-          mbar->addMenu (menu);
           c->set_action (new Action (menu), true);
+          prev_action = insert_action_after (mbar, prev_action, menu->menuAction ());
         } else {
           //  Move the action to the end if present in the menu already
           std::set<std::pair<size_t, QAction *> >::iterator a = present_actions.find (std::make_pair (id_from_action (c->menu ()->menuAction ()), c->menu ()->menuAction ()));
           if (a != present_actions.end ()) {
             if (s_can_move_menu) {
               mbar->removeAction (a->second);
-              mbar->addMenu (c->menu ());
+              insert_action_after (mbar, prev_action, a->second);
             }
+            prev_action = a->second;
             present_actions.erase (*a);
           } else {
-            mbar->addMenu (c->menu ());
+            prev_action = insert_action_after (mbar, prev_action, c->menu ()->menuAction ());
           }
         }
 
@@ -1036,17 +1059,20 @@ AbstractMenu::build (QMenuBar *mbar, QToolBar *tbar)
       }
 
     } else if (mbar) {
+
       //  Move the action to the end if present in the menu already
       std::set<std::pair<size_t, QAction *> >::iterator a = present_actions.find (std::make_pair (id_from_action (c->action ()->qaction ()), c->action ()->qaction ()));
       if (a != present_actions.end ()) {
         if (s_can_move_menu) {
           mbar->removeAction (a->second);
-          mbar->addAction (c->action ()->qaction ());
+          insert_action_after (mbar, prev_action, a->second);
         }
+        prev_action = a->second;
         present_actions.erase (*a);
       } else {
-        mbar->addAction (c->action ()->qaction ());
+        prev_action = insert_action_after (mbar, prev_action, c->action ()->qaction ());
       }
+
     }
 
   }
@@ -1068,6 +1094,8 @@ AbstractMenu::build (QMenu *m, std::list<AbstractMenuItem> &items)
     present_actions.insert (std::make_pair (id_from_action (*i), *i));
   }
 
+  QAction *prev_action = 0;
+
   for (std::list<AbstractMenuItem>::iterator c = items.begin (); c != items.end (); ++c) {
 
     if (c->has_submenu ()) {
@@ -1077,19 +1105,20 @@ AbstractMenu::build (QMenu *m, std::list<AbstractMenuItem> &items)
         //  menu with a given action. The action is provided by addMenu instead.
         QMenu *menu = new QMenu (mp_dispatcher->menu_parent_widget ());
         menu->setTitle (tl::to_qstring (c->action ()->get_title ()));
-        m->addMenu (menu);
         c->set_action (new Action (menu), true);
+        prev_action = insert_action_after (m, prev_action, menu->menuAction ());
       } else {
         //  Move the action to the end if present in the menu already
         std::set<std::pair<size_t, QAction *> >::iterator a = present_actions.find (std::make_pair (id_from_action (c->menu ()->menuAction ()), c->menu ()->menuAction ()));
         if (a != present_actions.end ()) {
           if (s_can_move_menu) {
             m->removeAction (a->second);
-            m->addMenu (c->menu ());
+            insert_action_after (m, prev_action, a->second);
           }
+          prev_action = a->second;
           present_actions.erase (*a);
         } else {
-          m->addMenu (c->menu ());
+          prev_action = insert_action_after (m, prev_action, c->menu ()->menuAction ());
         }
       }
 
@@ -1102,11 +1131,12 @@ AbstractMenu::build (QMenu *m, std::list<AbstractMenuItem> &items)
       if (a != present_actions.end ()) {
         if (s_can_move_menu) {
           m->removeAction (a->second);
-          m->addAction (c->action ()->qaction ());
+          insert_action_after (m, prev_action, a->second);
         }
+        prev_action = a->second;
         present_actions.erase (*a);
       } else {
-        m->addAction (c->action ()->qaction ());
+        prev_action = insert_action_after (m, prev_action, c->action ()->qaction ());
       }
 
     }
diff --git a/src/laybasic/laybasic/layBitmap.cc b/src/laybasic/laybasic/layBitmap.cc
index 1c9c76336..ad857de2e 100644
--- a/src/laybasic/laybasic/layBitmap.cc
+++ b/src/laybasic/laybasic/layBitmap.cc
@@ -380,7 +380,38 @@ Bitmap::fill (unsigned int y, unsigned int x1, unsigned int x2)
   }
 }
 
-struct PosCompareF 
+void
+Bitmap::clear (unsigned int y, unsigned int x1, unsigned int x2)
+{
+  unsigned int b1 = x1 / 32;
+
+  uint32_t *sl = scanline (y);
+  sl += b1;
+
+  unsigned int b = x2 / 32 - b1;
+  if (b == 0) {
+
+    *sl &= ~masks [x2 % 32] | masks [x1 % 32];
+
+  } else if (b > 0) {
+
+    *sl++ &= masks [x1 % 32];
+    while (b > 1) {
+      *sl++ = 0;
+      b--;
+    }
+
+    unsigned int m = masks [x2 % 32];
+    //  Hint: if x2==width and width%32==0, sl must not be accessed. This is guaranteed by
+    //  checking if m != 0.
+    if (m) {
+      *sl &= ~m;
+    }
+
+  }
+}
+
+struct PosCompareF
 {
   bool operator() (const RenderEdge &a, const RenderEdge &b) const
   {
diff --git a/src/laybasic/laybasic/layBitmap.h b/src/laybasic/laybasic/layBitmap.h
index e225134e5..07dc3bb2a 100644
--- a/src/laybasic/laybasic/layBitmap.h
+++ b/src/laybasic/laybasic/layBitmap.h
@@ -246,6 +246,17 @@ public:
    */
   void fill (unsigned int y, unsigned int x1, unsigned int x2);
 
+  /**
+   *  @brief Clears the given part of the scanline
+   *
+   *  Same as fill(), but resets the bits.
+   *
+   *  @param y The scanline
+   *  @param x1 The start coordinate
+   *  @param x2 The end coordinate
+   */
+  void clear (unsigned int y, unsigned int x1, unsigned int x2);
+
   /**
    *  @brief Merges the "from" bitmap into this
    *
diff --git a/src/laybasic/laybasic/layBrowserPanel.cc b/src/laybasic/laybasic/layBrowserPanel.cc
index 1da5393a7..3dd2393e2 100644
--- a/src/laybasic/laybasic/layBrowserPanel.cc
+++ b/src/laybasic/laybasic/layBrowserPanel.cc
@@ -22,9 +22,11 @@
 
 
 #include "layBrowserPanel.h"
+#include "layDispatcher.h"
 #include "tlExceptions.h"
 #include "tlInternational.h"
 #include "tlException.h"
+#include "tlString.h"
 
 #include "ui_BrowserPanel.h"
 
@@ -34,6 +36,10 @@
 #endif
 
 #include <QTreeWidgetItem>
+#include <QTextBlock>
+#include <QCompleter>
+#include <QStringListModel>
+#include <QScrollBar>
 
 namespace lay
 {
@@ -52,9 +58,44 @@ BrowserTextWidget::loadResource (int type, const QUrl &url)
 
 // -------------------------------------------------------------
 
+void
+BookmarkItem::read (tl::Extractor &ex)
+{
+  while (! ex.at_end () && ! ex.test (";")) {
+
+    std::string k, v;
+    ex.read_word (k);
+    ex.test (":");
+    ex.read_word_or_quoted (v, "+-.");
+    ex.test (",");
+
+    if (k == "url") {
+      url = v;
+    } else if (k == "title") {
+      title = v;
+    } else if (k == "position") {
+      tl::from_string (v, position);
+    }
+
+  }
+}
+
+std::string
+BookmarkItem::to_string () const
+{
+  std::string r;
+  r = "url:" + tl::to_quoted_string (url) + ",";
+  r += "title:" + tl::to_quoted_string (title) + ",";
+  r += "position:" + tl::to_string (position) + ";";
+  return r;
+}
+
+// -------------------------------------------------------------
+
 BrowserPanel::BrowserPanel (QWidget *parent)
   : QWidget (parent),
-    m_back_dm (this, &BrowserPanel::back)
+    m_back_dm (this, &BrowserPanel::back),
+    mp_dispatcher (0)
 {
   init ();
 }
@@ -72,21 +113,53 @@ BrowserPanel::init ()
   mp_ui->browser->setReadOnly (true);
   mp_ui->browser->set_panel (this);
   mp_ui->browser->setWordWrapMode (QTextOption::WordWrap);
+  mp_ui->browser->setLineWrapMode (QTextEdit::FixedPixelWidth);
+  QFontMetrics fm (font ());
+  int text_width = fm.boundingRect ('m').width () * 80;
+  mp_ui->browser->setLineWrapColumnOrWidth (text_width);
+
+  mp_ui->browser->addAction (mp_ui->action_find);
+  mp_ui->browser->addAction (mp_ui->action_bookmark);
+
+  mp_ui->browser_bookmark_view->addAction (mp_ui->action_delete_bookmark);
+  mp_ui->browser_bookmark_view->setContextMenuPolicy (Qt::ActionsContextMenu);
 
   connect (mp_ui->back_pb, SIGNAL (clicked ()), this, SLOT (back ()));
   connect (mp_ui->forward_pb, SIGNAL (clicked ()), this, SLOT (forward ()));
   connect (mp_ui->next_topic_pb, SIGNAL (clicked ()), this, SLOT (next ()));
   connect (mp_ui->prev_topic_pb, SIGNAL (clicked ()), this, SLOT (prev ()));
+  connect (mp_ui->bookmark_pb, SIGNAL (clicked ()), this, SLOT (bookmark ()));
   connect (mp_ui->home_pb, SIGNAL (clicked ()), this, SLOT (home ()));
-  connect (mp_ui->searchEdit, SIGNAL (returnPressed ()), this, SLOT (search_edited ()));
+  connect (mp_ui->search_edit, SIGNAL (textEdited (const QString &)), this, SLOT (search_text_changed (const QString &)));
+  connect (mp_ui->search_edit, SIGNAL (returnPressed ()), this, SLOT (search_edited ()));
+  connect (mp_ui->search_button, SIGNAL (clicked ()), this, SLOT (search_edited ()));
   connect (mp_ui->browser, SIGNAL (textChanged ()), this, SLOT (text_changed ()));
   connect (mp_ui->browser, SIGNAL (backwardAvailable (bool)), mp_ui->back_pb, SLOT (setEnabled (bool)));
   connect (mp_ui->browser, SIGNAL (forwardAvailable (bool)), mp_ui->forward_pb, SLOT (setEnabled (bool)));
   connect (mp_ui->outline_tree, SIGNAL (itemActivated (QTreeWidgetItem *, int)), this, SLOT (outline_item_clicked (QTreeWidgetItem *)));
+  connect (mp_ui->on_page_search_edit, SIGNAL (textChanged (const QString &)), this, SLOT (page_search_edited ()));
+  connect (mp_ui->search_close_button, SIGNAL (clicked ()), this, SLOT (page_search_edited ()), Qt::QueuedConnection);
+  connect (mp_ui->on_page_search_edit, SIGNAL (returnPressed ()), this, SLOT (page_search_next ()));
+  connect (mp_ui->on_page_search_next, SIGNAL (clicked ()), this, SLOT (page_search_next ()));
+  connect (mp_ui->action_find, SIGNAL (triggered ()), this, SLOT (find ()));
+  connect (mp_ui->action_bookmark, SIGNAL (triggered ()), this, SLOT (bookmark ()));
+  connect (mp_ui->action_delete_bookmark, SIGNAL (triggered ()), this, SLOT (delete_bookmark ()));
+  connect (mp_ui->browser_bookmark_view, SIGNAL (itemDoubleClicked (QTreeWidgetItem *, int)), this, SLOT (bookmark_item_selected (QTreeWidgetItem *)));
 
-  mp_ui->searchEdit->hide ();
+  mp_completer = new QCompleter (this);
+  mp_completer->setFilterMode (Qt::MatchStartsWith);
+  mp_completer->setCaseSensitivity (Qt::CaseInsensitive);
+  mp_completer->setCompletionMode (QCompleter::UnfilteredPopupCompletion);
+  mp_completer_model = new QStringListModel (mp_completer);
+  mp_completer->setModel (mp_completer_model);
+  mp_ui->search_edit->setCompleter (mp_completer);
+
+  mp_ui->search_frame->hide ();
+  mp_ui->search_edit->hide ();
 
   set_label (std::string ());
+
+  refresh_bookmark_list ();
 }
 
 BrowserPanel::~BrowserPanel ()
@@ -98,6 +171,37 @@ BrowserPanel::~BrowserPanel ()
   mp_ui = 0;
 }
 
+void
+BrowserPanel::set_dispatcher (lay::Dispatcher *dispatcher, const std::string &cfg_bookmarks)
+{
+  mp_dispatcher = dispatcher;
+  m_cfg_bookmarks = cfg_bookmarks;
+
+  m_bookmarks.clear ();
+
+  //  load the bookmarks
+  try {
+
+    if (mp_dispatcher) {
+
+      std::string v;
+      mp_dispatcher->config_get (m_cfg_bookmarks, v);
+
+      tl::Extractor ex (v.c_str ());
+      while (! ex.at_end ()) {
+        m_bookmarks.push_back (BookmarkItem ());
+        m_bookmarks.back ().read (ex);
+      }
+
+    }
+
+  } catch (...) {
+    //  exceptions ignored here
+  }
+
+  refresh_bookmark_list ();
+}
+
 std::string
 BrowserPanel::title () const
 {
@@ -110,6 +214,198 @@ BrowserPanel::url () const
   return m_cached_url;
 }
 
+void
+BrowserPanel::bookmark ()
+{
+  BookmarkItem bm;
+  bm.url = tl::to_string (mp_ui->browser->historyUrl (0).toString ());
+  QString title = mp_ui->browser->document ()->metaInformation (QTextDocument::DocumentTitle);
+  bm.title = tl::to_string (title);
+  bm.position = mp_ui->browser->verticalScrollBar ()->value ();
+
+  add_bookmark (bm);
+  refresh_bookmark_list ();
+  store_bookmarks ();
+}
+
+void
+BrowserPanel::store_bookmarks ()
+{
+  if (mp_dispatcher) {
+
+    std::string s;
+    for (std::list<BookmarkItem>::const_iterator i = m_bookmarks.begin (); i != m_bookmarks.end (); ++i) {
+      s += i->to_string ();
+    }
+
+    mp_dispatcher->config_set (m_cfg_bookmarks, s);
+
+  }
+}
+
+void
+BrowserPanel::bookmark_item_selected (QTreeWidgetItem *item)
+{
+  int index = mp_ui->browser_bookmark_view->indexOfTopLevelItem (item);
+  if (index < 0 || index >= int (m_bookmarks.size ())) {
+    return;
+  }
+
+  std::list<BookmarkItem>::iterator i = m_bookmarks.begin ();
+  for ( ; i != m_bookmarks.end () && index > 0; --index, ++i)
+    ;
+
+  if (i == m_bookmarks.end ()) {
+    return;
+  }
+
+  BookmarkItem bm = *i;
+  m_bookmarks.erase (i);
+  m_bookmarks.push_front (bm);
+
+  refresh_bookmark_list ();
+  store_bookmarks ();
+  load (bm.url);
+
+  mp_ui->browser->verticalScrollBar ()->setValue (bm.position);
+  mp_ui->browser_bookmark_view->topLevelItem (0)->setSelected (true);
+}
+
+void
+BrowserPanel::clear_bookmarks ()
+{
+  m_bookmarks.clear ();
+}
+
+void
+BrowserPanel::add_bookmark (const BookmarkItem &item)
+{
+  for (std::list<BookmarkItem>::iterator i = m_bookmarks.begin (); i != m_bookmarks.end (); ) {
+    std::list<BookmarkItem>::iterator ii = i;
+    ++ii;
+    if (*i == item) {
+      m_bookmarks.erase (i);
+    }
+    i = ii;
+  }
+  m_bookmarks.push_front (item);
+}
+
+void
+BrowserPanel::delete_bookmark ()
+{
+  QTreeWidgetItem *item = mp_ui->browser_bookmark_view->currentItem ();
+  if (! item) {
+    return;
+  }
+
+  int index = mp_ui->browser_bookmark_view->indexOfTopLevelItem (item);
+  std::list<BookmarkItem>::iterator i = m_bookmarks.begin ();
+  for ( ; i != m_bookmarks.end () && index > 0; --index, ++i)
+    ;
+
+  if (i != m_bookmarks.end ()) {
+    m_bookmarks.erase (i);
+    refresh_bookmark_list ();
+    store_bookmarks ();
+  }
+}
+
+void
+BrowserPanel::refresh_bookmark_list ()
+{
+  mp_ui->browser_bookmark_view->setVisible (! m_bookmarks.empty ());
+
+  mp_ui->browser_bookmark_view->clear ();
+  for (std::list<BookmarkItem>::const_iterator i = m_bookmarks.begin (); i != m_bookmarks.end (); ++i) {
+    QTreeWidgetItem *item = new QTreeWidgetItem (mp_ui->browser_bookmark_view);
+    item->setData (0, Qt::DisplayRole, tl::to_qstring (i->title));
+    item->setData (0, Qt::ToolTipRole, tl::to_qstring (i->title));
+    item->setData (0, Qt::DecorationRole, QIcon (":/bookmark_16.png"));
+  }
+}
+
+void
+BrowserPanel::find ()
+{
+  mp_ui->search_frame->show ();
+  mp_ui->on_page_search_edit->setFocus();
+}
+
+void
+BrowserPanel::page_search_edited ()
+{
+  m_search_selection.clear ();
+  m_search_index = -1;
+
+  if (! mp_ui->search_frame->isVisible () || mp_ui->on_page_search_edit->text ().size () < 2) {
+    mp_ui->browser->setExtraSelections (m_search_selection);
+    return;
+  }
+
+  QString search_text = mp_ui->on_page_search_edit->text ();
+
+  QTextDocument *doc = mp_ui->browser->document ();
+  for (QTextBlock b = doc->firstBlock (); b.isValid (); b = b.next ()) {
+
+    int from = 0;
+    int index;
+
+    QString t = b.text ();
+
+    while ((index = t.indexOf (search_text, from, Qt::CaseInsensitive)) >= 0) {
+
+      QTextCursor highlight (b);
+      highlight.movePosition (QTextCursor::NextCharacter, QTextCursor::MoveAnchor, index);
+      highlight.movePosition (QTextCursor::NextCharacter, QTextCursor::KeepAnchor, search_text.size ());
+
+      QTextEdit::ExtraSelection extra_selection;
+      extra_selection.cursor = highlight;
+      extra_selection.format.setBackground (QColor (255, 255, 160));
+      m_search_selection.push_back (extra_selection);
+
+      from = index + search_text.size ();
+
+    }
+
+  }
+
+  if (! m_search_selection.empty ()) {
+    m_search_index = 0;
+    mp_ui->browser->setExtraSelections (m_search_selection);
+    mp_ui->browser->setTextCursor (m_search_selection [m_search_index].cursor);
+  }
+}
+
+void
+BrowserPanel::page_search_next ()
+{
+  if (m_search_index >= 0) {
+
+    ++m_search_index;
+    if (m_search_index >= m_search_selection.size ()) {
+      m_search_index = 0;
+    }
+
+    mp_ui->browser->setTextCursor (m_search_selection [m_search_index].cursor);
+
+  }
+}
+
+void
+BrowserPanel::search_text_changed (const QString &text)
+{
+  QList<QString> strings;
+  if (! text.isEmpty () && mp_source.get ()) {
+    std::list<std::string> cl;
+    mp_source->search_completers (tl::to_string (text.toLower ()), cl);
+    for (std::list<std::string>::const_iterator i = cl.begin (); i != cl.end (); ++i) {
+      strings.push_back (tl::to_qstring (*i));
+    }
+  }
+  mp_completer_model->setStringList (strings);
+}
+
 void
 BrowserPanel::text_changed ()
 {
@@ -118,6 +414,9 @@ BrowserPanel::text_changed ()
     m_current_title = title;
     emit title_changed (title);
   }
+
+  //  refresh on-page search
+  page_search_edited ();
 }
 
 void
@@ -259,15 +558,15 @@ BrowserPanel::search (const std::string &s)
 void
 BrowserPanel::search_edited ()
 {
-  if (mp_ui->searchEdit->text ().size () > 0) {
+  if (mp_ui->search_edit->text ().size () > 0) {
     QUrl url (tl::to_qstring (m_search_url));
 #if QT_VERSION >= 0x050000
     QUrlQuery qi;
-    qi.addQueryItem (tl::to_qstring (m_search_query_item), mp_ui->searchEdit->text ());
+    qi.addQueryItem (tl::to_qstring (m_search_query_item), mp_ui->search_edit->text ());
     url.setQuery (qi);
 #else
     QList<QPair<QString, QString> > qi;
-    qi.push_back (QPair<QString, QString> (tl::to_qstring (m_search_query_item), mp_ui->searchEdit->text ()));
+    qi.push_back (QPair<QString, QString> (tl::to_qstring (m_search_query_item), mp_ui->search_edit->text ()));
     url.setQueryItems (qi);
 #endif
     load (url.toEncoded ().constData ());
@@ -279,7 +578,7 @@ BrowserPanel::set_search_url (const std::string &url, const std::string &query_i
 {
   m_search_url = url;
   m_search_query_item = query_item;
-  mp_ui->searchEdit->setVisible (! url.empty ());
+  mp_ui->search_edit->setVisible (! url.empty ());
 }
 
 void 
@@ -474,6 +773,12 @@ BrowserSource::get_outline (const std::string & /*url*/)
   return BrowserOutline ();
 }
 
+void
+BrowserSource::search_completers (const std::string & /*search_string*/, std::list<std::string> & /*completers*/)
+{
+  //  .. nothing here ..
+}
+
 std::string 
 BrowserSource::get (const std::string & /*url*/) 
 {
diff --git a/src/laybasic/laybasic/layBrowserPanel.h b/src/laybasic/laybasic/layBrowserPanel.h
index b974de658..d32366a18 100644
--- a/src/laybasic/laybasic/layBrowserPanel.h
+++ b/src/laybasic/laybasic/layBrowserPanel.h
@@ -30,12 +30,15 @@
 #include "gsiObject.h"
 
 #include <QTextBrowser>
+#include <QCompleter>
 
 #include <string>
 #include <list>
 #include <set>
 
 class QTreeWidgetItem;
+class QCompleter;
+class QStringListModel;
 
 namespace Ui
 {
@@ -46,6 +49,7 @@ namespace lay
 {
 
 class BrowserPanel;
+class Dispatcher;
 
 /**
  *  @brief Specifies the outline of the document
@@ -204,6 +208,11 @@ public:
    */
   virtual BrowserOutline get_outline (const std::string &url);
 
+  /**
+   *  @brief Gets the search completer items for a given search string
+   */
+  virtual void search_completers (const std::string &search_string, std::list<std::string> &completers);
+
   /**
    *  @brief Get the image for a given "int" URL in an image
    */
@@ -273,6 +282,26 @@ private:
   BrowserPanel *mp_panel;
 };
 
+/**
+ *  @brief A structure describing a bookmark item
+ */
+struct LAYBASIC_PUBLIC BookmarkItem
+{
+  BookmarkItem () : position (0) { }
+
+  bool operator== (const BookmarkItem &other) const
+  {
+    return url == other.url && position == other.position;
+  }
+
+  void read (tl::Extractor &ex);
+  std::string to_string () const;
+
+  std::string url;
+  std::string title;
+  int position;
+};
+
 /**
  *  @brief A specialisation of QWidget around a TextBrowser that allows loading a specific resource
  */
@@ -286,14 +315,26 @@ Q_OBJECT
 public:
   /**
    *  @brief Constructor
+   *
+   *  @param p The parent widget
    */
-  BrowserPanel (QWidget *p); 
+  BrowserPanel (QWidget *p);
 
   /**
    *  @brief Dtor
    */
   ~BrowserPanel ();
 
+  /**
+   *  @brief Connects the panel to a configuration dispatcher
+   *
+   *  Doing so allows storing bookmarks and retrieving them.
+   *
+   *  @param dispatcher If given, this interface will be used to retrieve and store the bookmark list
+   *  @param cfg_bookmarks If dispatcher is given, this will be the configuration key to store the bookmarks
+   */
+  void set_dispatcher (lay::Dispatcher *dispatcher, const std::string &cfg_bookmarks);
+
   /**
    *  @brief Connect to a source object
    *  If "
@@ -385,10 +426,25 @@ public slots:
    */
   void home ();
 
+  /**
+   *  @brief "find" activated
+   */
+  void find ();
+
+  /**
+   *  @brief "bookmark" activated
+   */
+  void bookmark();
+
 protected slots:
+  void page_search_edited ();
+  void page_search_next();
+  void search_text_changed(const QString &text);
   void search_edited ();
   void text_changed ();
   void outline_item_clicked (QTreeWidgetItem *item);
+  void bookmark_item_selected (QTreeWidgetItem *item);
+  void delete_bookmark ();
 
 protected:
   virtual QVariant loadResource (int type, const QUrl &url);
@@ -408,8 +464,19 @@ private:
   tl::DeferredMethod<BrowserPanel> m_back_dm;
   std::string m_search_url, m_search_query_item;
   QString m_current_title;
+  QList<QTextEdit::ExtraSelection> m_search_selection;
+  int m_search_index;
+  QCompleter *mp_completer;
+  QStringListModel *mp_completer_model;
+  std::list<BookmarkItem> m_bookmarks;
+  lay::Dispatcher *mp_dispatcher;
+  std::string m_cfg_bookmarks;
 
   void init ();
+  void clear_bookmarks ();
+  void add_bookmark (const BookmarkItem &item);
+  void refresh_bookmark_list ();
+  void store_bookmarks ();
 };
 
 }
diff --git a/src/laybasic/laybasic/layCellTreeModel.cc b/src/laybasic/laybasic/layCellTreeModel.cc
index b1c91977e..52486cbec 100644
--- a/src/laybasic/laybasic/layCellTreeModel.cc
+++ b/src/laybasic/laybasic/layCellTreeModel.cc
@@ -28,6 +28,7 @@
 #include "dbPCellVariant.h"
 #include "dbLibraryProxy.h"
 #include "dbLibrary.h"
+#include "dbLibraryManager.h"
 
 #include <QTreeView>
 #include <QPalette>
@@ -604,14 +605,53 @@ CellTreeModel::mimeData(const QModelIndexList &indexes) const
 {
   for (QModelIndexList::const_iterator i = indexes.begin (); i != indexes.end (); ++i) {
 
-    if (i->isValid()) {
+    if (! i->isValid()) {
+      continue;
+    }
+
+    if (is_pcell (*i)) {
+
+      lay::CellDragDropData data (mp_layout, mp_library, pcell_id (*i), true);
+      return data.to_mime_data ();
+
+    } else {
+
+      const db::Cell *c = cell (*i);
+      if (c) {
+
+        //  resolve library proxies
+        const db::Layout *layout = mp_layout;
+        const db::Library *library = mp_library;
+
+        const db::LibraryProxy *lib_proxy;
+        while (layout != 0 && (lib_proxy = dynamic_cast <const db::LibraryProxy *> (c)) != 0) {
+
+          const db::Library *lib = db::LibraryManager::instance ().lib (lib_proxy->lib_id ());
+          if (! lib) {
+            break;
+          }
+
+          library = lib;
+          layout = &lib->layout ();
+
+          if (layout->is_valid_cell_index (lib_proxy->library_cell_index ())) {
+            c = &layout->cell (lib_proxy->library_cell_index ());
+          } else {
+            c = 0;
+          }
+
+        }
+
+        //  identify pcell variants and turn them into PCell drag targets
+        const db::PCellVariant *pcell_var = dynamic_cast<const db::PCellVariant *> (c);
+        if (pcell_var) {
+          lay::CellDragDropData data (layout, library, pcell_var->pcell_id (), true, pcell_var->parameters ());
+          return data.to_mime_data ();
+        } else if (c) {
+          lay::CellDragDropData data (layout, library, c->cell_index (), false);
+          return data.to_mime_data ();
+        }
 
-      if (is_pcell (*i)) {
-        lay::CellDragDropData data (mp_layout, mp_library, pcell_id (*i), true);
-        return data.to_mime_data ();
-      } else if (cell (*i)) {
-        lay::CellDragDropData data (mp_layout, mp_library, cell_index (*i), false);
-        return data.to_mime_data ();
       }
 
     }
diff --git a/src/laybasic/laybasic/layD25TechnologyComponent.cc b/src/laybasic/laybasic/layD25TechnologyComponent.cc
new file mode 100644
index 000000000..c004b4a1f
--- /dev/null
+++ b/src/laybasic/laybasic/layD25TechnologyComponent.cc
@@ -0,0 +1,102 @@
+
+/*
+
+  KLayout Layout Viewer
+  Copyright (C) 2006-2020 Matthias Koefferlein
+
+  This program is free software; you can redistribute it and/or modify
+  it under the terms of the GNU General Public License as published by
+  the Free Software Foundation; either version 2 of the License, or
+  (at your option) any later version.
+
+  This program is distributed in the hope that it will be useful,
+  but WITHOUT ANY WARRANTY; without even the implied warranty of
+  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+  GNU General Public License for more details.
+
+  You should have received a copy of the GNU General Public License
+  along with this program; if not, write to the Free Software
+  Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
+
+*/
+
+
+#include "laybasicConfig.h"
+#include "dbD25TechnologyComponent.h"
+#include "layD25TechnologyComponent.h"
+
+#include <QResource>
+#include <QBuffer>
+
+namespace lay
+{
+
+D25TechnologyComponentEditor::D25TechnologyComponentEditor (QWidget *parent)
+  : TechnologyComponentEditor (parent)
+{
+  setupUi (this);
+
+  //  TODO: activate_help_links (mp_ui->help_label);
+
+  QResource res (tl::to_qstring (":/syntax/d25_text.xml"));
+  QByteArray data ((const char *) res.data (), int (res.size ()));
+  if (res.isCompressed ()) {
+    data = qUncompress (data);
+  }
+
+  QBuffer input (&data);
+  input.open (QIODevice::ReadOnly);
+  mp_hl_basic_attributes.reset (new GenericSyntaxHighlighterAttributes ());
+  mp_hl_attributes.reset (new GenericSyntaxHighlighterAttributes (mp_hl_basic_attributes.get ()));
+  lay::GenericSyntaxHighlighter *hl = new GenericSyntaxHighlighter (src_te, input, mp_hl_attributes.get ());
+  input.close ();
+
+  hl->setDocument (src_te->document ());
+
+  connect (src_te, SIGNAL (cursorPositionChanged ()), this, SLOT (cursor_position_changed ()));
+}
+
+void
+D25TechnologyComponentEditor::cursor_position_changed ()
+{
+  int line = src_te->textCursor ().block ().firstLineNumber () + 1;
+  lnum_label->setText (tl::to_qstring (tl::sprintf (tl::to_string (tr ("Line %d")), line)));
+}
+
+void
+D25TechnologyComponentEditor::commit ()
+{
+  db::D25TechnologyComponent *data = dynamic_cast <db::D25TechnologyComponent *> (tech_component ());
+  if (! data) {
+    return;
+  }
+
+  std::string src = tl::to_string (src_te->toPlainText ());
+  data->compile_from_source (src);
+}
+
+void
+D25TechnologyComponentEditor::setup ()
+{
+  db::D25TechnologyComponent *data = dynamic_cast <db::D25TechnologyComponent *> (tech_component ());
+  if (! data) {
+    return;
+  }
+
+  src_te->setPlainText (tl::to_qstring (data->src ()));
+}
+
+class D25TechnologyComponentEditorProvider
+  : public lay::TechnologyEditorProvider
+{
+public:
+  virtual lay::TechnologyComponentEditor *create_editor (QWidget *parent) const
+  {
+    return new D25TechnologyComponentEditor (parent);
+  }
+};
+
+static tl::RegisteredClass<lay::TechnologyEditorProvider> editor_decl (new D25TechnologyComponentEditorProvider (), 3100, "d25");
+
+} // namespace lay
+
diff --git a/src/laybasic/laybasic/layD25TechnologyComponent.h b/src/laybasic/laybasic/layD25TechnologyComponent.h
new file mode 100644
index 000000000..206838b70
--- /dev/null
+++ b/src/laybasic/laybasic/layD25TechnologyComponent.h
@@ -0,0 +1,57 @@
+
+/*
+
+  KLayout Layout Viewer
+  Copyright (C) 2006-2020 Matthias Koefferlein
+
+  This program is free software; you can redistribute it and/or modify
+  it under the terms of the GNU General Public License as published by
+  the Free Software Foundation; either version 2 of the License, or
+  (at your option) any later version.
+
+  This program is distributed in the hope that it will be useful,
+  but WITHOUT ANY WARRANTY; without even the implied warranty of
+  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+  GNU General Public License for more details.
+
+  You should have received a copy of the GNU General Public License
+  along with this program; if not, write to the Free Software
+  Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
+
+*/
+
+
+#ifndef HDR_layD25TechnologyComponent
+#define HDR_layD25TechnologyComponent
+
+#include "ui_D25TechnologyComponentEditor.h"
+#include "layTechnology.h"
+#include "layGenericSyntaxHighlighter.h"
+
+#include <memory>
+
+namespace lay {
+
+class D25TechnologyComponentEditor
+  : public lay::TechnologyComponentEditor,
+    public Ui::D25TechnologyComponentEditor
+{
+Q_OBJECT
+
+public:
+  D25TechnologyComponentEditor (QWidget *parent);
+
+  void commit ();
+  void setup ();
+
+private slots:
+  void cursor_position_changed ();
+
+private:
+  std::auto_ptr<lay::GenericSyntaxHighlighterAttributes> mp_hl_attributes, mp_hl_basic_attributes;
+};
+
+}
+
+#endif
+
diff --git a/src/laybasic/laybasic/layEditable.cc b/src/laybasic/laybasic/layEditable.cc
index c2ef0fa38..0a86a8c3e 100644
--- a/src/laybasic/laybasic/layEditable.cc
+++ b/src/laybasic/laybasic/layEditable.cc
@@ -80,6 +80,11 @@ Editables::Editables (db::Manager *manager)
 Editables::~Editables ()
 {
   cancel_edits ();
+
+  if (mp_properties_dialog) {
+    delete mp_properties_dialog;
+    mp_properties_dialog = 0;
+  }
 }
 
 void 
@@ -444,6 +449,14 @@ Editables::select (const db::DPoint &pt, lay::Editable::SelectionMode mode)
   signal_selection_changed ();
 }
 
+void
+Editables::repeat_selection (Editable::SelectionMode mode)
+{
+  if (m_last_selected_point.is_point ()) {
+    select (m_last_selected_point, mode);
+  }
+}
+
 bool 
 Editables::begin_move (const db::DPoint &p, lay::angle_constraint_type ac)
 {
@@ -602,9 +615,8 @@ Editables::cancel_edits ()
 {
   //  close the property dialog
   if (mp_properties_dialog) {
-    delete mp_properties_dialog;
+    mp_properties_dialog->hide ();
   }
-  mp_properties_dialog = 0;
 
   //  cancel any edit operations
   for (iterator e = begin (); e != end (); ++e) {
@@ -615,7 +627,15 @@ Editables::cancel_edits ()
 void
 Editables::show_properties (QWidget *parent)
 {
-  cancel_edits ();
+  if (selection_size () == 0) {
+    //  try to use the transient selection for the real one
+    transient_to_selection ();
+  }
+
+  //  re-create a new properties dialog
+  if (mp_properties_dialog) {
+    delete mp_properties_dialog;
+  }
   mp_properties_dialog = new lay::PropertiesDialog (parent, manager (), this);
   mp_properties_dialog->show ();
 }
diff --git a/src/laybasic/laybasic/layEditable.h b/src/laybasic/laybasic/layEditable.h
index a5d6831e7..b60ed500a 100644
--- a/src/laybasic/laybasic/layEditable.h
+++ b/src/laybasic/laybasic/layEditable.h
@@ -493,6 +493,13 @@ public:
    */
   void select (const db::DPoint &pt, Editable::SelectionMode mode);
 
+  /**
+   *  @brief Repeat the previous selection
+   *
+   *  This method will not do anything if there is no previous, click-at selection.
+   */
+  void repeat_selection (Editable::SelectionMode mode);
+
   /**
    *  @brief Start "move" operation
    *
diff --git a/src/laybasic/laybasic/layEditorOptionsFrame.cc b/src/laybasic/laybasic/layEditorOptionsFrame.cc
new file mode 100644
index 000000000..283462ff1
--- /dev/null
+++ b/src/laybasic/laybasic/layEditorOptionsFrame.cc
@@ -0,0 +1,70 @@
+
+/*
+
+  KLayout Layout Viewer
+  Copyright (C) 2006-2020 Matthias Koefferlein
+
+  This program is free software; you can redistribute it and/or modify
+  it under the terms of the GNU General Public License as published by
+  the Free Software Foundation; either version 2 of the License, or
+  (at your option) any later version.
+
+  This program is distributed in the hope that it will be useful,
+  but WITHOUT ANY WARRANTY; without even the implied warranty of
+  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+  GNU General Public License for more details.
+
+  You should have received a copy of the GNU General Public License
+  along with this program; if not, write to the Free Software
+  Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
+
+*/
+
+#include "layEditorOptionsFrame.h"
+#include "layEditorOptionsPage.h"
+#include "layEditorOptionsPages.h"
+#include "layPlugin.h"
+#include "layLayoutView.h"
+
+#include <QVBoxLayout>
+
+namespace lay
+{
+
+EditorOptionsFrame::EditorOptionsFrame (QWidget *parent)
+  : QFrame (parent), mp_pages (0)
+{
+  setObjectName (QString::fromUtf8 ("editor_options_frame"));
+
+  QVBoxLayout *left_frame_ly = new QVBoxLayout (this);
+  left_frame_ly->setMargin (0);
+  left_frame_ly->setSpacing (0);
+}
+
+EditorOptionsFrame::~EditorOptionsFrame ()
+{
+  //  .. nothing yet ..
+}
+
+void
+EditorOptionsFrame::populate (LayoutView *view)
+{
+  std::vector<lay::EditorOptionsPage *> prop_dialog_pages;
+  for (tl::Registrar<lay::PluginDeclaration>::iterator cls = tl::Registrar<lay::PluginDeclaration>::begin (); cls != tl::Registrar<lay::PluginDeclaration>::end (); ++cls) {
+    cls->get_editor_options_pages (prop_dialog_pages, view, view->dispatcher ());
+  }
+
+  for (std::vector<lay::EditorOptionsPage *>::const_iterator op = prop_dialog_pages.begin (); op != prop_dialog_pages.end (); ++op) {
+    (*op)->activate (false);
+  }
+
+  if (mp_pages) {
+    delete mp_pages;
+  }
+
+  mp_pages = new lay::EditorOptionsPages (this, prop_dialog_pages, view);
+  layout ()->addWidget (mp_pages);
+  setFocusProxy (mp_pages);
+}
+
+}
diff --git a/src/laybasic/laybasic/layEditorOptionsFrame.h b/src/laybasic/laybasic/layEditorOptionsFrame.h
new file mode 100644
index 000000000..5b17d3d0f
--- /dev/null
+++ b/src/laybasic/laybasic/layEditorOptionsFrame.h
@@ -0,0 +1,55 @@
+
+/*
+
+  KLayout Layout Viewer
+  Copyright (C) 2006-2020 Matthias Koefferlein
+
+  This program is free software; you can redistribute it and/or modify
+  it under the terms of the GNU General Public License as published by
+  the Free Software Foundation; either version 2 of the License, or
+  (at your option) any later version.
+
+  This program is distributed in the hope that it will be useful,
+  but WITHOUT ANY WARRANTY; without even the implied warranty of
+  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+  GNU General Public License for more details.
+
+  You should have received a copy of the GNU General Public License
+  along with this program; if not, write to the Free Software
+  Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
+
+*/
+
+#ifndef HDR_layEditorOptionsFrame
+#define HDR_layEditorOptionsFrame
+
+#include "laybasicCommon.h"
+#include <QFrame>
+
+namespace lay
+{
+
+class EditorOptionsPages;
+class LayoutView;
+
+class LAYBASIC_PUBLIC EditorOptionsFrame
+  : public QFrame
+{
+public:
+  EditorOptionsFrame (QWidget *parent);
+  virtual ~EditorOptionsFrame ();
+
+  void populate (LayoutView *view);
+
+  EditorOptionsPages *pages_widget () const
+  {
+    return mp_pages;
+  }
+
+public:
+  EditorOptionsPages *mp_pages;
+};
+
+}
+
+#endif
diff --git a/src/laybasic/laybasic/layEditorOptionsPage.cc b/src/laybasic/laybasic/layEditorOptionsPage.cc
new file mode 100644
index 000000000..cc4a92d91
--- /dev/null
+++ b/src/laybasic/laybasic/layEditorOptionsPage.cc
@@ -0,0 +1,65 @@
+
+/*
+
+  KLayout Layout Viewer
+  Copyright (C) 2006-2020 Matthias Koefferlein
+
+  This program is free software; you can redistribute it and/or modify
+  it under the terms of the GNU General Public License as published by
+  the Free Software Foundation; either version 2 of the License, or
+  (at your option) any later version.
+
+  This program is distributed in the hope that it will be useful,
+  but WITHOUT ANY WARRANTY; without even the implied warranty of
+  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+  GNU General Public License for more details.
+
+  You should have received a copy of the GNU General Public License
+  along with this program; if not, write to the Free Software
+  Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
+
+*/
+
+
+#include "tlInternational.h"
+#include "layEditorOptionsPage.h"
+#include "layEditorOptionsPages.h"
+
+namespace lay
+{
+
+// ------------------------------------------------------------------
+//  EditorOptionsPage implementation
+
+EditorOptionsPage::EditorOptionsPage (lay::Dispatcher *dispatcher)
+  : QWidget (0), mp_owner (0), m_active (true), mp_plugin_declaration (0), mp_dispatcher (dispatcher)
+{
+  //  nothing yet ..
+}
+
+EditorOptionsPage::~EditorOptionsPage ()
+{
+  set_owner (0);
+}
+
+void
+EditorOptionsPage::set_owner (EditorOptionsPages *owner)
+{
+  if (mp_owner) {
+    mp_owner->unregister_page (this);
+  }
+  mp_owner = owner;
+}
+
+void
+EditorOptionsPage::activate (bool active)
+{
+  if (m_active != active) {
+    m_active = active;
+    if (mp_owner) {
+      mp_owner->activate_page (this);
+    }
+  }
+}
+
+}
diff --git a/src/laybasic/laybasic/layEditorOptionsPage.h b/src/laybasic/laybasic/layEditorOptionsPage.h
new file mode 100644
index 000000000..3ee70b1a0
--- /dev/null
+++ b/src/laybasic/laybasic/layEditorOptionsPage.h
@@ -0,0 +1,84 @@
+
+/*
+
+  KLayout Layout Viewer
+  Copyright (C) 2006-2020 Matthias Koefferlein
+
+  This program is free software; you can redistribute it and/or modify
+  it under the terms of the GNU General Public License as published by
+  the Free Software Foundation; either version 2 of the License, or
+  (at your option) any later version.
+
+  This program is distributed in the hope that it will be useful,
+  but WITHOUT ANY WARRANTY; without even the implied warranty of
+  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+  GNU General Public License for more details.
+
+  You should have received a copy of the GNU General Public License
+  along with this program; if not, write to the Free Software
+  Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
+
+*/
+
+#ifndef HDR_layEditorOptionsPage
+#define HDR_layEditorOptionsPage
+
+#include "laybasicCommon.h"
+
+#include <QWidget>
+
+namespace lay
+{
+
+class PluginDeclaration;
+class Dispatcher;
+class Plugin;
+class EditorOptionsPages;
+
+/**
+ *  @brief The base class for a object properties page
+ */
+class LAYBASIC_PUBLIC EditorOptionsPage
+  : public QWidget
+{
+Q_OBJECT
+
+public:
+  EditorOptionsPage (lay::Dispatcher *dispatcher);
+  virtual ~EditorOptionsPage ();
+
+  virtual std::string title () const = 0;
+  virtual int order () const = 0;
+  virtual void apply (lay::Dispatcher * /*root*/) { }
+  virtual void setup (lay::Dispatcher * /*root*/) { }
+  virtual void commit_recent (lay::Dispatcher * /*root*/) { }
+
+  bool active () const { return m_active; }
+  void activate (bool active);
+  void set_owner (EditorOptionsPages *owner);
+
+  const lay::PluginDeclaration *plugin_declaration () const { return mp_plugin_declaration; }
+  void set_plugin_declaration (const lay::PluginDeclaration *pd) { mp_plugin_declaration = pd; }
+
+protected slots:
+  void edited ()
+  {
+    apply (dispatcher ());
+  }
+
+protected:
+  lay::Dispatcher *dispatcher () const
+  {
+    return mp_dispatcher;
+  }
+
+private:
+  EditorOptionsPages *mp_owner;
+  bool m_active;
+  const lay::PluginDeclaration *mp_plugin_declaration;
+  lay::Dispatcher *mp_dispatcher;
+};
+
+}
+
+#endif
diff --git a/src/laybasic/laybasic/layEditorOptionsPages.cc b/src/laybasic/laybasic/layEditorOptionsPages.cc
new file mode 100644
index 000000000..0cc55fb62
--- /dev/null
+++ b/src/laybasic/laybasic/layEditorOptionsPages.cc
@@ -0,0 +1,215 @@
+
+/*
+
+  KLayout Layout Viewer
+  Copyright (C) 2006-2020 Matthias Koefferlein
+
+  This program is free software; you can redistribute it and/or modify
+  it under the terms of the GNU General Public License as published by
+  the Free Software Foundation; either version 2 of the License, or
+  (at your option) any later version.
+
+  This program is distributed in the hope that it will be useful,
+  but WITHOUT ANY WARRANTY; without even the implied warranty of
+  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+  GNU General Public License for more details.
+
+  You should have received a copy of the GNU General Public License
+  along with this program; if not, write to the Free Software
+  Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
+
+*/
+
+
+#include "tlInternational.h"
+#include "layEditorOptionsPages.h"
+#include "tlExceptions.h"
+#include "layPlugin.h"
+#include "layLayoutView.h"
+#include "layQtTools.h"
+
+#include <QHBoxLayout>
+#include <QVBoxLayout>
+#include <QTabWidget>
+#include <QToolButton>
+#include <QCompleter>
+#include <QLineEdit>
+
+namespace lay
+{
+
+// ------------------------------------------------------------------
+//  EditorOptionsPages implementation
+
+struct EOPCompareOp
+{
+  bool operator() (lay::EditorOptionsPage *a, lay::EditorOptionsPage *b) const
+  {
+    return a->order () < b->order ();
+  }
+};
+
+EditorOptionsPages::EditorOptionsPages (QWidget *parent, const std::vector<lay::EditorOptionsPage *> &pages, lay::Dispatcher *dispatcher)
+  : QFrame (parent), mp_dispatcher (dispatcher)
+{
+  QVBoxLayout *ly1 = new QVBoxLayout (this);
+  ly1->setMargin (0);
+
+  mp_pages = new QTabWidget (this);
+  ly1->addWidget (mp_pages);
+
+  m_pages = pages;
+  for (std::vector <lay::EditorOptionsPage *>::const_iterator p = m_pages.begin (); p != m_pages.end (); ++p) {
+    (*p)->set_owner (this);
+  }
+
+  update (0);
+  setup ();
+}
+
+EditorOptionsPages::~EditorOptionsPages ()
+{
+  while (m_pages.size () > 0) {
+    delete m_pages.front ();
+  }
+}
+
+void
+EditorOptionsPages::focusInEvent (QFocusEvent * /*event*/)
+{
+  //  Sends the focus to the current page's last focus owner
+  if (mp_pages->currentWidget () && mp_pages->currentWidget ()->focusWidget ()) {
+    mp_pages->currentWidget ()->focusWidget ()->setFocus ();
+    }
+}
+
+bool EditorOptionsPages::has_content () const
+{
+  for (std::vector <lay::EditorOptionsPage *>::const_iterator p = m_pages.begin (); p != m_pages.end (); ++p) {
+    //  NOTE: we ignore unspecific pages because they are always visible and don't contribute specific content
+    if ((*p)->active () && (*p)->plugin_declaration () != 0) {
+      return true;
+    }
+  }
+  return false;
+}
+
+void  
+EditorOptionsPages::unregister_page (lay::EditorOptionsPage *page)
+{
+  std::vector <lay::EditorOptionsPage *> pages;
+  for (std::vector <lay::EditorOptionsPage *>::const_iterator p = m_pages.begin (); p != m_pages.end (); ++p) {
+    if (*p != page) {
+      pages.push_back (*p);
+    }
+  }
+  m_pages = pages;
+  update (0);
+}
+
+void  
+EditorOptionsPages::activate_page (lay::EditorOptionsPage *page)
+{
+  try {
+    if (page->active ()) {
+      page->setup (mp_dispatcher);
+    }
+  } catch (...) {
+    //  catch any errors related to configuration file errors etc.
+  }
+
+  update (page);
+}
+
+void   
+EditorOptionsPages::update (lay::EditorOptionsPage *page)
+{
+  std::vector <lay::EditorOptionsPage *> sorted_pages = m_pages;
+  std::sort (sorted_pages.begin (), sorted_pages.end (), EOPCompareOp ());
+
+  if (! page && m_pages.size () > 0) {
+    page = m_pages.back ();
+  }
+
+  while (mp_pages->count () > 0) {
+    mp_pages->removeTab (0);
+  }
+  int index = -1;
+  for (std::vector <lay::EditorOptionsPage *>::iterator p = sorted_pages.begin (); p != sorted_pages.end (); ++p) {
+    if ((*p)->active ()) {
+      if ((*p) == page) {
+        index = mp_pages->count ();
+      }
+      mp_pages->addTab (*p, tl::to_qstring ((*p)->title ()));
+    } else {
+      (*p)->setParent (0);
+    }
+  }
+  if (index < 0) {
+    index = mp_pages->currentIndex ();
+  }
+  if (index >= int (mp_pages->count ())) {
+    index = mp_pages->count () - 1;
+  }
+  mp_pages->setCurrentIndex (index);
+
+  setVisible (mp_pages->count () > 0);
+}
+
+void 
+EditorOptionsPages::setup ()
+{
+  try {
+
+    for (std::vector <lay::EditorOptionsPage *>::iterator p = m_pages.begin (); p != m_pages.end (); ++p) {
+      if ((*p)->active ()) {
+        (*p)->setup (mp_dispatcher);
+      }
+    }
+
+    //  make the display consistent with the status (this is important for 
+    //  PCell parameters where the PCell may be asked to modify the parameters)
+    do_apply ();
+
+  } catch (...) {
+    //  catch any errors related to configuration file errors etc.
+  }
+}
+
+void 
+EditorOptionsPages::do_apply ()
+{
+  for (std::vector <lay::EditorOptionsPage *>::iterator p = m_pages.begin (); p != m_pages.end (); ++p) {
+    if ((*p)->active ()) {
+      //  NOTE: we apply to the root dispatcher, so other dispatchers (views) get informed too.
+      (*p)->apply (mp_dispatcher->dispatcher ());
+    }
+  }
+}
+
+void 
+EditorOptionsPages::apply ()
+{
+BEGIN_PROTECTED
+  do_apply ();
+END_PROTECTED_W (this)
+}
+
+// ------------------------------------------------------------------
+//  Indicates an error on a line edit
+
+template <class Value>
+static void configure_from_line_edit (lay::Dispatcher *dispatcher, QLineEdit *le, const std::string &cfg_name)
+{
+  try {
+    Value value = Value (0);
+    tl::from_string (tl::to_string (le->text ()), value);
+    dispatcher->config_set (cfg_name, tl::to_string (value));
+    lay::indicate_error (le, 0);
+  } catch (tl::Exception &ex) {
+    lay::indicate_error (le, &ex);
+  }
+}
+
+}
+
diff --git a/src/laybasic/laybasic/layEditorOptionsPages.h b/src/laybasic/laybasic/layEditorOptionsPages.h
new file mode 100644
index 000000000..d20351e0a
--- /dev/null
+++ b/src/laybasic/laybasic/layEditorOptionsPages.h
@@ -0,0 +1,85 @@
+
+/*
+
+  KLayout Layout Viewer
+  Copyright (C) 2006-2020 Matthias Koefferlein
+
+  This program is free software; you can redistribute it and/or modify
+  it under the terms of the GNU General Public License as published by
+  the Free Software Foundation; either version 2 of the License, or
+  (at your option) any later version.
+
+  This program is distributed in the hope that it will be useful,
+  but WITHOUT ANY WARRANTY; without even the implied warranty of
+  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+  GNU General Public License for more details.
+
+  You should have received a copy of the GNU General Public License
+  along with this program; if not, write to the Free Software
+  Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
+
+*/
+
+
+#ifndef HDR_layEditorOptionsPages
+#define HDR_layEditorOptionsPages
+
+#include "laybasicCommon.h"
+#include "layEditorOptionsPage.h"
+
+#include <tlVariant.h>
+
+#include <QFrame>
+#include <vector>
+#include <string>
+
+class QTabWidget;
+class QLabel;
+
+namespace lay
+{
+
+class PluginDeclaration;
+class Dispatcher;
+class Plugin;
+
+/**
+ *  @brief The object properties dialog
+ */
+class LAYBASIC_PUBLIC EditorOptionsPages
+  : public QFrame
+{
+Q_OBJECT
+
+public:
+  EditorOptionsPages (QWidget *parent, const std::vector<lay::EditorOptionsPage *> &pages, lay::Dispatcher *root);
+  ~EditorOptionsPages ();
+
+  void unregister_page (lay::EditorOptionsPage *page);
+  void activate_page (lay::EditorOptionsPage *page);
+  void focusInEvent (QFocusEvent *event);
+
+  const std::vector <lay::EditorOptionsPage *> &pages () const
+  {
+    return m_pages;
+  }
+
+  bool has_content () const;
+
+public slots:
+  void apply ();
+  void setup ();
+
+private:
+  std::vector <lay::EditorOptionsPage *> m_pages;
+  lay::Dispatcher *mp_dispatcher;
+  QTabWidget *mp_pages;
+
+  void update (lay::EditorOptionsPage *page);
+  void do_apply ();
+};
+
+}
+
+#endif
+
diff --git a/src/laybasic/laybasic/layEditorServiceBase.cc b/src/laybasic/laybasic/layEditorServiceBase.cc
new file mode 100644
index 000000000..51f93429d
--- /dev/null
+++ b/src/laybasic/laybasic/layEditorServiceBase.cc
@@ -0,0 +1,297 @@
+
+/*
+
+  KLayout Layout Viewer
+  Copyright (C) 2006-2020 Matthias Koefferlein
+
+  This program is free software; you can redistribute it and/or modify
+  it under the terms of the GNU General Public License as published by
+  the Free Software Foundation; either version 2 of the License, or
+  (at your option) any later version.
+
+  This program is distributed in the hope that it will be useful,
+  but WITHOUT ANY WARRANTY; without even the implied warranty of
+  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+  GNU General Public License for more details.
+
+  You should have received a copy of the GNU General Public License
+  along with this program; if not, write to the Free Software
+  Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
+
+*/
+
+#include "layEditorServiceBase.h"
+#include "layViewport.h"
+#include "layLayoutView.h"
+#include "laybasicConfig.h"
+#include "layConverters.h"
+
+namespace lay
+{
+
+// --------------------------------------------------------------------------------------
+
+template <size_t num_pts>
+static void
+make_circle (double r, const db::DPoint &center, db::DPolygon &poly, bool as_hole)
+{
+  db::DPoint pts [num_pts];
+  for (size_t i = 0; i < num_pts; ++i) {
+    double x = r * cos (M_PI * 2.0 * double (i) / double (num_pts));
+    double y = r * sin (M_PI * 2.0 * double (i) / double (num_pts));
+    pts [i] = center + db::DVector (x, y);
+  }
+
+  if (! as_hole) {
+    poly.assign_hull (pts, pts + num_pts);
+  } else {
+    poly.insert_hole (pts, pts + num_pts);
+  }
+}
+
+class TrackingCursorBase
+  : public lay::ViewObject
+{
+public:
+  TrackingCursorBase (lay::EditorServiceBase *service, lay::ViewObjectWidget *widget)
+    : lay::ViewObject (widget, false), mp_service (service)
+  { }
+
+  uint32_t cursor_color (lay::ViewObjectCanvas &canvas) const
+  {
+    QColor color;
+    if (mp_service) {
+      color = mp_service->tracking_cursor_color ();
+    }
+    if (! color.isValid ()) {
+      color = canvas.foreground_color ();
+    }
+    return color.rgb ();
+  }
+
+  virtual void render (const lay::Viewport &vp, lay::ViewObjectCanvas &canvas)
+  {
+    if (mp_service && mp_service->tracking_cursor_enabled ()) {
+      do_render (vp, canvas);
+    }
+  }
+
+protected:
+  virtual void do_render (const lay::Viewport &vp, lay::ViewObjectCanvas &canvas) = 0;
+
+private:
+  lay::EditorServiceBase *mp_service;
+};
+
+class MouseCursorViewObject
+  : public TrackingCursorBase
+{
+public:
+  MouseCursorViewObject (lay::EditorServiceBase *service, lay::ViewObjectWidget *widget, const db::DPoint &pt, bool solid)
+    : TrackingCursorBase (service, widget), m_pt (pt), m_solid (solid)
+  { }
+
+protected:
+  virtual void do_render (const lay::Viewport &vp, lay::ViewObjectCanvas &canvas)
+  {
+    int dither_pattern = 0; // solid
+    int cross_dither_pattern = 6;  // dotted
+
+    int lw = int (0.5 + 1.0 / canvas.resolution ());
+
+    std::vector <lay::ViewOp> ops;
+    ops.resize (1);
+    ops[0] = lay::ViewOp (cursor_color (canvas), lay::ViewOp::Copy, 0, (unsigned int) dither_pattern, 0, lay::ViewOp::Rect, lw, 0);
+    lay::CanvasPlane *plane = canvas.plane (ops);
+
+    ops[0] = lay::ViewOp (cursor_color (canvas), lay::ViewOp::Copy, 0, (unsigned int) cross_dither_pattern, 0, lay::ViewOp::Rect, lw, 0);
+    lay::CanvasPlane *cross_plane = canvas.plane (ops);
+
+    lay::Renderer &r = canvas.renderer ();
+
+    double rad = 4.0 / canvas.resolution () / vp.trans ().mag ();
+
+    db::DPolygon c;
+    if (! m_solid) {
+      make_circle<size_t (16)> (rad, m_pt, c, false);
+      r.draw (c, vp.trans (), 0, plane, 0, 0);
+    } else {
+      make_circle<size_t (16)> (rad * 2, m_pt, c, false);
+      r.draw (c, vp.trans (), 0, plane, 0, 0);
+      make_circle<size_t (16)> (rad, m_pt, c, false);
+      r.draw (c, vp.trans (), 0, plane, 0, 0);
+    }
+
+    r.draw (db::DEdge (m_pt + db::DVector (0, -rad * 4), m_pt + db::DVector (0, rad * 4)), vp.trans (), 0, cross_plane, 0, 0);
+    r.draw (db::DEdge (m_pt + db::DVector (-rad * 4, 0), m_pt + db::DVector (rad * 4, 0)), vp.trans (), 0, cross_plane, 0, 0);
+  }
+
+private:
+  db::DPoint m_pt;
+  bool m_solid;
+};
+
+class EdgeMarkerViewObject
+  : public TrackingCursorBase
+{
+public:
+  EdgeMarkerViewObject (lay::EditorServiceBase *service, lay::ViewObjectWidget *widget, const db::DEdge &edge, bool solid)
+    : TrackingCursorBase (service, widget), m_edge (edge), m_solid (solid)
+  { }
+
+protected:
+  virtual void do_render (const lay::Viewport &vp, lay::ViewObjectCanvas &canvas)
+  {
+    if (m_edge.is_degenerate ()) {
+      return;
+    }
+
+    int dashed_style = 2;
+    int solid_style = 0;
+
+    int lw = int (0.5 + 1.0 / canvas.resolution ());
+
+    std::vector <lay::ViewOp> ops;
+    ops.resize (1);
+    ops[0] = lay::ViewOp (cursor_color (canvas), lay::ViewOp::Copy, solid_style, 0, 0, lay::ViewOp::Rect, lw, 0);
+    lay::CanvasPlane *arrow_plane = canvas.plane (ops);
+
+    ops[0] = lay::ViewOp (cursor_color (canvas), lay::ViewOp::Copy, m_solid ? solid_style : dashed_style, 1, 0, lay::ViewOp::Rect, lw, 0);
+    lay::CanvasPlane *edge_plane = canvas.plane (ops);
+
+    lay::Renderer &r = canvas.renderer ();
+    r.draw (m_edge, vp.trans (), 0, edge_plane, 0, 0);
+
+    double arrow_length = 12.0 / canvas.resolution () / vp.trans ().mag ();
+
+    double arrow_width_half = arrow_length * 0.25882; // sin(15 deg)
+    db::DVector n = db::DVector (m_edge.dy (), -m_edge.dx ()) * (arrow_width_half / m_edge.length ());
+    db::DVector d = db::DVector (m_edge.dx (), m_edge.dy ()) * (arrow_length / m_edge.length ());
+
+    if (m_edge.length () < 2 * arrow_length) {
+
+      r.draw (db::DEdge (m_edge.p1 () - n, m_edge.p1 () + n), vp.trans (), 0, arrow_plane, 0, 0);
+      r.draw (db::DEdge (m_edge.p2 () - n, m_edge.p2 () + n), vp.trans (), 0, arrow_plane, 0, 0);
+
+    } else {
+
+      db::DPoint pts[3];
+      db::DPolygon p;
+
+      pts[0] = m_edge.p1 ();
+      pts[1] = m_edge.p1 () + d - n;
+      pts[2] = m_edge.p1 () + d + n;
+
+      p.assign_hull (pts, pts + 3);
+      r.draw (p, vp.trans (), 0, arrow_plane, 0, 0);
+
+      pts[0] = m_edge.p2 ();
+      pts[1] = m_edge.p2 () - d + n;
+      pts[2] = m_edge.p2 () - d - n;
+
+      p.assign_hull (pts, pts + 3);
+      r.draw (p, vp.trans (), 0, arrow_plane, 0, 0);
+
+    }
+  }
+
+private:
+  db::DEdge m_edge;
+  bool m_solid;
+};
+
+// --------------------------------------------------------------------------------------
+
+EditorServiceBase::EditorServiceBase (lay::LayoutView *view)
+  : lay::ViewService (view->view_object_widget ()),
+    lay::Editable (view),
+    lay::Plugin (view),
+    m_cursor_enabled (true)
+{
+  //  .. nothing yet ..
+}
+
+EditorServiceBase::~EditorServiceBase ()
+{
+  clear_mouse_cursors ();
+}
+
+void
+EditorServiceBase::add_mouse_cursor (const db::DPoint &pt, bool emphasize)
+{
+  m_mouse_cursor_markers.push_back (new MouseCursorViewObject (this, widget (), pt, emphasize));
+}
+
+void
+EditorServiceBase::add_edge_marker (const db::DEdge &e, bool emphasize)
+{
+  m_mouse_cursor_markers.push_back (new EdgeMarkerViewObject (this, widget (), e, emphasize));
+}
+
+void
+EditorServiceBase::clear_mouse_cursors ()
+{
+  for (std::vector<lay::ViewObject *>::iterator r = m_mouse_cursor_markers.begin (); r != m_mouse_cursor_markers.end (); ++r) {
+    delete *r;
+  }
+  m_mouse_cursor_markers.clear ();
+}
+
+void
+EditorServiceBase::mouse_cursor_from_snap_details (const lay::PointSnapToObjectResult &snap_details)
+{
+  clear_mouse_cursors ();
+
+  add_mouse_cursor (snap_details.snapped_point,
+                    snap_details.object_snap == lay::PointSnapToObjectResult::ObjectVertex ||
+                    (snap_details.object_snap == lay::PointSnapToObjectResult::ObjectUnspecific && snap_details.object_ref.is_degenerate ()));
+
+  if (snap_details.object_snap == lay::PointSnapToObjectResult::ObjectEdge ||
+      (snap_details.object_snap == lay::PointSnapToObjectResult::ObjectUnspecific && ! snap_details.object_ref.is_degenerate ())) {
+    add_edge_marker (snap_details.object_ref, false);
+  }
+}
+
+bool
+EditorServiceBase::configure (const std::string &name, const std::string &value)
+{
+  bool needs_update = false;
+
+  if (name == cfg_tracking_cursor_color) {
+
+    QColor color;
+    lay::ColorConverter ().from_string (value, color);
+
+    if (color != m_cursor_color) {
+      m_cursor_color = color;
+      needs_update = true;
+    }
+
+  } else if (name == cfg_tracking_cursor_enabled) {
+
+    bool f = m_cursor_enabled;
+    tl::from_string (value, f);
+    if (f != m_cursor_enabled) {
+      m_cursor_enabled = f;
+      needs_update = true;
+    }
+
+  }
+
+  if (needs_update) {
+    for (std::vector<lay::ViewObject *>::iterator r = m_mouse_cursor_markers.begin (); r != m_mouse_cursor_markers.end (); ++r) {
+      (*r)->redraw ();
+    }
+  }
+
+  //  NOTE: we don't take the value as other services may be interested too.
+  return false;
+}
+
+void
+EditorServiceBase::deactivated ()
+{
+  clear_mouse_cursors ();
+}
+
+}
diff --git a/src/laybasic/laybasic/layEditorServiceBase.h b/src/laybasic/laybasic/layEditorServiceBase.h
new file mode 100644
index 000000000..7735b9deb
--- /dev/null
+++ b/src/laybasic/laybasic/layEditorServiceBase.h
@@ -0,0 +1,122 @@
+
+/*
+
+  KLayout Layout Viewer
+  Copyright (C) 2006-2020 Matthias Koefferlein
+
+  This program is free software; you can redistribute it and/or modify
+  it under the terms of the GNU General Public License as published by
+  the Free Software Foundation; either version 2 of the License, or
+  (at your option) any later version.
+
+  This program is distributed in the hope that it will be useful,
+  but WITHOUT ANY WARRANTY; without even the implied warranty of
+  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+  GNU General Public License for more details.
+
+  You should have received a copy of the GNU General Public License
+  along with this program; if not, write to the Free Software
+  Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
+
+*/
+
+
+#ifndef HDR_layEditorServiceBase
+#define HDR_layEditorServiceBase
+
+#include "laybasicCommon.h"
+#include "layEditable.h"
+#include "layViewObject.h"
+#include "layPlugin.h"
+
+namespace lay
+{
+
+/**
+ *  @brief A generic base class for an editor service
+ *
+ *  This class offers common services such as a mouse cursor.
+ */
+class LAYBASIC_PUBLIC EditorServiceBase
+  : public lay::ViewService,
+    public lay::Editable,
+    public lay::Plugin
+{
+public: 
+  /**
+   *  @brief Constructor
+   */
+  EditorServiceBase (lay::LayoutView *view);
+
+  /**
+   *  @brief Destructor
+   */
+  ~EditorServiceBase ();
+
+  /**
+   *  @brief Obtain the lay::ViewService interface
+   */
+  lay::ViewService *view_service_interface ()
+  {
+    return this;
+  }
+
+  /**
+   *  @brief Obtain the lay::Editable interface
+   */
+  lay::Editable *editable_interface ()
+  {
+    return this;
+  }
+
+  /**
+   *  @brief Adds a mouse cursor to the given point
+   */
+  void add_mouse_cursor (const db::DPoint &pt, bool emphasize = false);
+
+  /**
+   *  @brief Adds an edge marker for the given edge
+   */
+  void add_edge_marker (const db::DEdge &e, bool emphasize);
+
+  /**
+   *  @brief Resets the mouse cursor
+   */
+  void clear_mouse_cursors ();
+
+  /**
+   *  @brief Provides a nice mouse tracking cursor from the given snap details
+   */
+  void mouse_cursor_from_snap_details (const lay::PointSnapToObjectResult &snap_details);
+
+  /**
+   *  @brief Gets the tracking cursor color
+   */
+  QColor tracking_cursor_color () const
+  {
+    return m_cursor_color;
+  }
+
+  /**
+   *  @brief Gets a value indicating whether the tracking cursor is enabled
+   */
+  bool tracking_cursor_enabled () const
+  {
+    return m_cursor_enabled;
+  }
+
+protected:
+  virtual bool configure (const std::string &name, const std::string &value);
+  virtual void deactivated ();
+
+private:
+  //  The marker representing the mouse cursor
+  std::vector<lay::ViewObject *> m_mouse_cursor_markers;
+  QColor m_cursor_color;
+  bool m_cursor_enabled;
+};
+
+}
+
+#endif
+
diff --git a/src/laybasic/laybasic/layFinder.cc b/src/laybasic/laybasic/layFinder.cc
index 378b0a8f7..62369082f 100644
--- a/src/laybasic/laybasic/layFinder.cc
+++ b/src/laybasic/laybasic/layFinder.cc
@@ -62,7 +62,7 @@ static int inst_point_sel_tests = 10000;
 
 Finder::Finder (bool point_mode, bool top_level_sel)
   : m_min_level (0), m_max_level (0),
-    mp_layout (0), mp_view (0), m_cv_index (0), m_point_mode (point_mode), m_top_level_sel (top_level_sel)
+    mp_layout (0), mp_view (0), m_cv_index (0), m_point_mode (point_mode), m_catch_all (false), m_top_level_sel (top_level_sel)
 {
   m_distance = std::numeric_limits<double>::max ();
 }
@@ -564,41 +564,32 @@ ShapeFinder::visit_cell (const db::Cell &cell, const db::Box &search_box, const
 
           if (match) {
 
+            lay::ObjectInstPath found;
+            found.set_cv_index (m_cv_index);
+            found.set_topcell (m_topcell);
+            found.assign_path (path ().begin (), path ().end ());
+            found.set_layer (*l);
+            found.set_shape (*shape);
+
             if (mp_excludes) {
 
               //  with an exclude list first create the selection item so we can check
               //  if it's part of the exclude set.
 
-              lay::ObjectInstPath found;
-              found.set_cv_index (m_cv_index);
-              found.set_topcell (m_topcell);
-              found.assign_path (path ().begin (), path ().end ());
-              found.set_layer (*l);
-              found.set_shape (*shape);
-
               //  in point mode just store the found object that has the least "distance" and is
               //  not in the exclude set
-              if (mp_excludes->find (found) == mp_excludes->end () && closer (d)) {
+              match = (mp_excludes->find (found) == mp_excludes->end ());
 
-                if (m_founds.empty ()) {
-                  m_founds.push_back (found);
-                } else {
-                  m_founds.front () = found;
-                }
-              }
+            }
 
-            } else if (closer (d)) {
+            if (match && (catch_all () || closer (d))) {
 
               //  in point mode just store that found that has the least "distance"
-              if (m_founds.empty ()) {
-                m_founds.push_back (lay::ObjectInstPath ());
+              if (m_founds.empty () || catch_all ()) {
+                m_founds.push_back (found);
               }
 
-              m_founds.back ().set_cv_index (m_cv_index);
-              m_founds.back ().set_topcell (m_topcell);
-              m_founds.back ().assign_path (path ().begin (), path ().end ());
-              m_founds.back ().set_layer (*l);
-              m_founds.back ().set_shape (*shape);
+              m_founds.back () = found;
 
             }
 
@@ -854,52 +845,38 @@ InstFinder::visit_cell (const db::Cell &cell, const db::Box &search_box, const d
 
           if (match) {
 
+            lay::ObjectInstPath found;
+            found.set_cv_index (m_cv_index);
+            found.set_topcell (m_topcell);
+            found.assign_path (path ().begin (), path ().end ());
+
+            //  add the selected instance as the last element of the path
+            db::InstElement el;
+            el.inst_ptr = *inst;
+            if (! m_full_arrays) {
+              el.array_inst = p;
+            }
+            found.add_path (el);
+
             if (mp_excludes) {
 
               //  with an exclude list first create the selection item so we can check
               //  if it's part of the exclude set.
 
-              lay::ObjectInstPath found;
-              found.set_cv_index (m_cv_index);
-              found.set_topcell (m_topcell);
-              found.assign_path (path ().begin (), path ().end ());
-
-              //  add the selected instance as the last element of the path
-              db::InstElement el;
-              el.inst_ptr = *inst;
-              if (! m_full_arrays) {
-                el.array_inst = p;
-              }
-              found.add_path (el);
-
               //  in point mode just store the found object that has the least "distance" and is
               //  not in the exclude set
-              if (mp_excludes->find (found) == mp_excludes->end () && closer (d)) {
-                if (m_founds.empty ()) {
-                  m_founds.push_back (found);
-                } else {
-                  m_founds.front () = found;
-                }
-              }
+              match = (mp_excludes->find (found) == mp_excludes->end ());
 
-            } else if (closer (d)) {
+            }
+
+            if (match && (catch_all () || closer (d))) {
 
               //  in point mode just store that found that has the least "distance"
-              if (m_founds.empty ()) {
+              if (m_founds.empty () || catch_all ()) {
                 m_founds.push_back (lay::ObjectInstPath ());
               }
 
-              m_founds.back ().set_cv_index (m_cv_index);
-              m_founds.back ().set_topcell (m_topcell);
-              m_founds.back ().assign_path (path ().begin (), path ().end ());
-
-              //  add the selected instance as the last element of the path
-              db::InstElement el;
-              el.inst_ptr = *inst;
-              if (! m_full_arrays) {
-                el.array_inst = p;
-              }
-              m_founds.back ().add_path (el);
+              m_founds.back () = found;
 
             }
 
diff --git a/src/laybasic/laybasic/layFinder.h b/src/laybasic/laybasic/layFinder.h
index c32a78d9e..84c4aa6a7 100644
--- a/src/laybasic/laybasic/layFinder.h
+++ b/src/laybasic/laybasic/layFinder.h
@@ -58,13 +58,42 @@ public:
    *
    *  The point_mode is true, if the finder is supposed to operate in "point mode".
    *  In point mode, the center of the search region is the reference point. In 
-   *  non-point mode, every relevant found inside the search region should be 
-   *  recorded. 
+   *  non-point mode, every relevant found inside the search region will be
+   *  recorded (also see point_mode method).
    *  The base class implementation just stores this flag and provides a read
    *  accessor with the point_mode () method.
    */
   Finder (bool point_mode, bool top_level_sel);
 
+  /**
+   *  @brief Gets a flag indicating whether point mode is enabled
+   *  If point mode is enabled in the constructor, the first will check for objects overlapping the
+   *  point (rather than being inside the box) and by default select a single object only.
+   *  See also "set_catch_all".
+   */
+  bool point_mode () const
+  {
+    return m_point_mode;
+  }
+
+  /**
+   *  @brief Gets a flag indicating the capture all founds even in point mode
+   */
+  bool catch_all () const
+  {
+    return m_catch_all;
+  }
+
+  /**
+   *  @brief Sets a flag indicating the capture all founds even in point mode
+   *  By default, in point mode only the closest found is returned. To catch all
+   *  founds in point mode too, set this flag to true.
+   */
+  void set_catch_all (bool f)
+  {
+    m_catch_all = f;
+  }
+
   /**
    *  @brief Destructor (just provided to please the compiler)
    */
@@ -87,11 +116,6 @@ protected:
     return m_layers;
   }
 
-  bool point_mode () const
-  {
-    return m_point_mode;
-  }
-
   const std::vector<db::InstElement> &path () const
   {
     return m_path;
@@ -168,6 +192,7 @@ private:
   std::vector<int> m_layers;
   double m_distance;
   bool m_point_mode;
+  bool m_catch_all;
   bool m_top_level_sel;
   db::box_convert <db::CellInst> m_box_convert;
   db::box_convert <db::Cell> m_cell_box_convert;
diff --git a/src/laybasic/laybasic/layLayerControlPanel.cc b/src/laybasic/laybasic/layLayerControlPanel.cc
index be8eda762..b0038635d 100644
--- a/src/laybasic/laybasic/layLayerControlPanel.cc
+++ b/src/laybasic/laybasic/layLayerControlPanel.cc
@@ -60,36 +60,6 @@
 namespace lay
 {
 
-// --------------------------------------------------------------------
-//  LCPTreeItemDelegate declaration & implementation
-
-/**
- *  @brief A layer tree widget helper class
- *
- *  A specialization of the ItemDelegate that bypasses the computation
- *  of sizeHint and returns the pixmap's size directly for higher
- *  performance.
- */
-
-class LCPItemDelegate : public QItemDelegate
-{
-public:
-  LCPItemDelegate (QWidget *parent) 
-    : QItemDelegate (parent)
-  { }
-
-private:
-  virtual QSize 
-  sizeHint (const QStyleOptionViewItem &style, const QModelIndex &index) const
-  {
-    if (index.column () == 0) {
-      return QSize (40, 16);
-    } else {
-      return QItemDelegate::sizeHint (style, index);
-    }
-  }
-};
-
 // --------------------------------------------------------------------
 //  LCPTreeWidget declaration & implementation
 
@@ -98,7 +68,6 @@ LCPTreeWidget::LCPTreeWidget (QWidget *parent, lay::LayerTreeModel *model, const
 {
   setObjectName (QString::fromUtf8 (name));
   setModel (model);
-  setItemDelegate (new LCPItemDelegate (this));
 #if QT_VERSION >= 0x040200
   setAllColumnsShowFocus (true);
 #endif
@@ -326,24 +295,21 @@ LayerControlPanel::LayerControlPanel (lay::LayoutView *view, db::Manager *manage
 
   mp_model = new lay::LayerTreeModel (this, view);
   mp_layer_list = new LCPTreeWidget (this, mp_model, "layer_tree");
-  mp_model->set_font (mp_layer_list->font ());
-  /*
-   * At least with Qt 4.2.x setting uniform row heights has a strange side effect: 
-   * If a range is selected and the first selection is scrolled out of view, the 
-   * range does not include the first element after having clicked at the second.
   mp_layer_list->setUniformRowHeights (true);
-  */
+  mp_model->set_font (mp_layer_list->font ());
+  mp_layer_list->setIconSize (mp_model->icon_size ());
+
   l->addWidget (mp_layer_list);
   connect (mp_layer_list, SIGNAL (double_clicked (const QModelIndex &, Qt::KeyboardModifiers)), this, SLOT (double_clicked (const QModelIndex &, Qt::KeyboardModifiers)));
   connect (mp_layer_list, SIGNAL (collapsed (const QModelIndex &)), this, SLOT (group_collapsed (const QModelIndex &)));
   connect (mp_layer_list, SIGNAL (expanded (const QModelIndex &)), this, SLOT (group_expanded (const QModelIndex &)));
   connect (mp_layer_list, SIGNAL (search_triggered (const QString &)), this, SLOT (search_triggered (const QString &)));
+  connect (mp_layer_list->selectionModel (), SIGNAL (currentChanged (const QModelIndex &, const QModelIndex &)), this, SLOT (current_index_changed (const QModelIndex &)));
   mp_layer_list->setContextMenuPolicy (Qt::CustomContextMenu);
   connect (mp_layer_list, SIGNAL(customContextMenuRequested (const QPoint &)), this, SLOT (context_menu (const QPoint &)));
   mp_layer_list->header ()->hide ();
   mp_layer_list->setSelectionMode (QTreeView::ExtendedSelection);
   mp_layer_list->setRootIsDecorated (false);
-  mp_layer_list->setIconSize (QSize (32, 16));
   //  Custom resize mode makes the columns as narrow as possible
 #if QT_VERSION >= 0x050000
   mp_layer_list->header ()->setSectionResizeMode (QHeaderView::ResizeToContents);
@@ -539,16 +505,14 @@ LayerControlPanel::cm_insert ()
 
     BEGIN_PROTECTED_CLEANUP
 
-    transaction (tl::to_string (QObject::tr ("Insert views")));
+    transaction (tl::to_string (QObject::tr ("Insert layer view")));
 
     props.set_source (tl::to_string (n));
     mp_view->init_layer_properties (props);
+
     const LayerPropertiesNode &lp = mp_view->insert_layer (sel, props);
 
-    if (transacting ()) {
-      manager ()->queue (this, new LayerSelectionClearOp ());
-    }
-    mp_layer_list->set_current (sel);
+    set_current_layer (sel);
 
     commit ();
 
@@ -599,18 +563,12 @@ LayerControlPanel::cm_group ()
 
     mp_view->insert_layer (ins_pos, node);
 
-    if (transacting ()) {
-      manager ()->queue (this, new LayerSelectionClearOp ());
-    }
+    set_current_layer (*sel.rbegin ());
 
     commit ();
 
-    end_updates ();
-
     emit order_changed ();
 
-    mp_layer_list->set_current (*sel.rbegin ());
-
   }
 
   END_PROTECTED_CLEANUP { recover (); }
@@ -1941,8 +1899,14 @@ LayerControlPanel::do_update_content ()
 }
 
 void
-LayerControlPanel::set_current_layer (const lay::LayerPropertiesConstIterator &l) const
+LayerControlPanel::set_current_layer (const lay::LayerPropertiesConstIterator &l)
 {
+  if (transacting ()) {
+    manager ()->queue (this, new LayerSelectionClearOp ());
+  }
+
+  end_updates ();
+
   mp_layer_list->set_current (l);
 }
 
@@ -2070,6 +2034,17 @@ LayerControlPanel::update_required (int f)
   m_do_update_content_dm ();
 }
 
+void
+LayerControlPanel::current_index_changed (const QModelIndex &index)
+{
+  lay::LayerPropertiesConstIterator iter = mp_model->iterator (index);
+  if (! iter.is_null () && ! iter.at_end ()) {
+    emit current_layer_changed (iter);
+  } else {
+    emit current_layer_changed (lay::LayerPropertiesConstIterator ());
+  }
+}
+
 void
 LayerControlPanel::group_collapsed (const QModelIndex &index)
 {
diff --git a/src/laybasic/laybasic/layLayerControlPanel.h b/src/laybasic/laybasic/layLayerControlPanel.h
index d7caea7a5..7276bdfbe 100644
--- a/src/laybasic/laybasic/layLayerControlPanel.h
+++ b/src/laybasic/laybasic/layLayerControlPanel.h
@@ -250,7 +250,7 @@ public:
    *
    *  This will also select this layer.
    */
-  void set_current_layer (const lay::LayerPropertiesConstIterator &l) const;
+  void set_current_layer (const lay::LayerPropertiesConstIterator &l);
 
   /**
    *  @brief Return the current layer index
@@ -284,6 +284,7 @@ public:
 signals:
   void order_changed ();
   void tab_changed ();
+  void current_layer_changed (const lay::LayerPropertiesConstIterator &iter);
 
 public slots:
   void cm_new_tab ();
@@ -321,6 +322,7 @@ public slots:
   void tab_context_menu (const QPoint &pt);  
   void group_collapsed (const QModelIndex &index);
   void group_expanded (const QModelIndex &index);
+  void current_index_changed (const QModelIndex &index);
   void up_clicked ();
   void upup_clicked ();
   void down_clicked ();
diff --git a/src/laybasic/laybasic/layLayerTreeModel.cc b/src/laybasic/laybasic/layLayerTreeModel.cc
index 3a6ce2f77..c622bf5e4 100644
--- a/src/laybasic/laybasic/layLayerTreeModel.cc
+++ b/src/laybasic/laybasic/layLayerTreeModel.cc
@@ -32,6 +32,7 @@
 #include <QTreeView>
 #include <QModelIndex>
 #include <QString>
+#include <QFontInfo>
 
 #include <string.h>
 
@@ -558,6 +559,161 @@ LayerTreeModel::empty_within_view_predicate (const QModelIndex &index) const
   }
 }
 
+LAYBASIC_PUBLIC
+QIcon
+LayerTreeModel::icon_for_layer (const lay::LayerPropertiesConstIterator &iter, lay::LayoutView *view, unsigned int w, unsigned int h, unsigned int di_off, bool no_state)
+{
+  h = std::max ((unsigned int) 16, h);
+  w = std::max ((unsigned int) 16, w);
+
+  lay::color_t def_color   = 0x808080;
+  lay::color_t fill_color  = iter->has_fill_color (true)  ? iter->eff_fill_color (true)  : def_color;
+  lay::color_t frame_color = iter->has_frame_color (true) ? iter->eff_frame_color (true) : def_color;
+
+  QImage image (w, h, QImage::Format_ARGB32);
+  image.fill (view->background_color ().rgb ());
+
+  //  upper scanline is a dummy one
+  uint32_t *sl0 = (uint32_t *) image.scanLine (0);
+  uint32_t transparent = QColor (Qt::transparent).rgba ();
+  for (size_t i = 0; i < w; ++i) {
+    *sl0++ = transparent;
+  }
+
+  //  TODO: adjust the resolution according to the oversampling mode
+  lay::Bitmap fill (w, h, 1.0);
+  lay::Bitmap frame (w, h, 1.0);
+  lay::Bitmap text (w, h, 1.0);
+  lay::Bitmap vertex (w, h, 1.0);
+
+  unsigned int wp = w - 1;
+
+  if (! no_state && ! iter->visible (true)) {
+
+    wp = w / 4;
+
+    //  Show the arrow if it is invisible also locally.
+    if (! iter->visible (false)) {
+
+      unsigned int aw = h / 4;
+      unsigned int ap = w / 2 - 1;
+      for (unsigned int i = 0; i <= aw; ++i) {
+        text.fill (h / 2 - 1 - i, ap, ap + aw - i + 1);
+        text.fill (h / 2 - 1 + i, ap, ap + aw - i + 1);
+      }
+
+    }
+
+  }
+
+  if (! no_state && view->no_stipples ()) {
+    //  Show a partial stipple pattern only for "no stipple" mode
+    for (unsigned int i = 1; i < h - 2; ++i) {
+      fill.fill (i, w - 1 - w / 4, w);
+    }
+  } else {
+    for (unsigned int i = 1; i < h - 2; ++i) {
+      fill.fill (i, w - 1 - wp, w);
+    }
+  }
+
+  int lw = iter->width (true);
+  if (lw < 0) {
+    //  default line width is 0 for parents and 1 for leafs
+    lw = iter->has_children () ? 0 : 1;
+  }
+
+  int p0 = lw / 2;
+  p0 = std::max (0, std::min (int (w / 4 - 1), p0));
+
+  int p1 = (lw - 1) / 2;
+  p1 = std::max (0, std::min (int (w / 4 - 1), p1));
+
+  int p0x = p0, p1x = p1;
+  unsigned int ddx = 0;
+  unsigned int ddy = h - 2 - p1 - p0;
+  if (iter->xfill (true)) {
+    ddx = wp - p0 - p1 - 1;
+  }
+  unsigned int d = ddx / 2;
+
+  frame.fill (p0, w - 1 - (wp - p1), w);
+  frame.fill (h - 2 - p1, w - 1 - (wp - p1), w);
+
+  for (unsigned int i = p0; i < h - 2; ++i) {
+
+    frame.fill (i, w - 1 - p0, w - p0);
+    frame.fill (i, w - 1 - (wp - p1), w - (wp - p1));
+    frame.fill (i, w - 1 - p0x, w - p0x);
+    frame.fill (i, w - 1 - (wp - p1x), w - (wp - p1x));
+
+    while (d < ddx) {
+      d += ddy;
+      frame.fill (i, w - 1 - p0x, w - p0x);
+      frame.fill (i, w - 1 - (wp - p1x), w - (wp - p1x));
+      ++p0x;
+      ++p1x;
+    }
+
+    if (d >= ddx) {
+      d -= ddx;
+    }
+
+  }
+
+  if (! no_state && ! iter->valid (true)) {
+
+    unsigned int bp = w - 1 - ((w * 7) / 8 - 1);
+    unsigned int be = bp + h / 2;
+    unsigned int bw = h / 4 - 1;
+    unsigned int by = h / 2 - 1;
+
+    for (unsigned int i = 0; i < bw + 2; ++i) {
+      fill.clear (by - i, bp - 1, be);
+      fill.clear (by + i, bp - 1, be);
+    }
+
+    for (unsigned int i = 0; i < bw; ++i) {
+      text.fill (by - i, bp + bw - i - 1, bp + bw - i + 1);
+      text.fill (by - i - 1, bp + bw - i - 1, bp + bw - i + 1);
+      text.fill (by - i, bp + bw + i, bp + bw + i + 2);
+      text.fill (by - i - 1, bp + bw + i, bp + bw + i + 2);
+      text.fill (by + i, bp + bw - i - 1, bp + bw - i + 1);
+      text.fill (by + i + 1, bp + bw - i - 1, bp + bw - i + 1);
+      text.fill (by + i, bp + bw + i, bp + bw + i + 2);
+      text.fill (by + i + 1, bp + bw + i, bp + bw + i + 2);
+    }
+
+  }
+
+  vertex.fill (h / 2 - 1, w - 1 - wp / 2, w - wp / 2);
+
+  lay::ViewOp::Mode mode = lay::ViewOp::Copy;
+
+  //  create fill
+  single_bitmap_to_image (lay::ViewOp (fill_color, mode, 0, iter->eff_dither_pattern (true), di_off), fill, &image, view->dither_pattern (), view->line_styles (), w, h);
+  //  create frame
+  if (lw == 0) {
+    single_bitmap_to_image (lay::ViewOp (frame_color, mode, 0 /*solid line*/, 2 /*dotted*/, 0), frame, &image, view->dither_pattern (), view->line_styles (), w, h);
+  } else {
+    single_bitmap_to_image (lay::ViewOp (frame_color, mode, iter->eff_line_style (true), 0, 0, lay::ViewOp::Rect, lw), frame, &image, view->dither_pattern (), view->line_styles (), w, h);
+  }
+  //  create text
+  single_bitmap_to_image (lay::ViewOp (frame_color, mode, 0, 0, 0), text, &image, view->dither_pattern (), view->line_styles (), w, h);
+  //  create vertex
+  single_bitmap_to_image (lay::ViewOp (frame_color, mode, 0, 0, 0, lay::ViewOp::Cross, iter->marked (true) ? 9/*mark size*/ : 0), vertex, &image, view->dither_pattern (), view->line_styles (),  w, h);
+
+  QPixmap pixmap = QPixmap::fromImage (image); // Qt 4.6.0 workaround
+  return QIcon (pixmap);
+}
+
+QSize
+LayerTreeModel::icon_size () const
+{
+  unsigned int is = ((QFontInfo (m_font).pixelSize () + 15) / 16) * 16;
+  return QSize (is * 2, is);
+}
+
 QVariant 
 LayerTreeModel::data (const QModelIndex &index, int role) const 
 {
@@ -568,6 +724,16 @@ LayerTreeModel::data (const QModelIndex &index, int role) const
 
       return QVariant ();
 
+    } else if (role == Qt::SizeHintRole) {
+
+      if (index.column () == 0) {
+        //  NOTE: for some reason, the widget clips the icon when inside a tree and needs a some what bigger width ..
+        QSize is = icon_size ();
+        return QVariant (is + QSize (is.width () / 4, 0));
+      } else {
+        return QVariant ();
+      }
+
     } else if (role == Qt::DisplayRole || role == Qt::EditRole) {
 
       if (index.column () == 1) {
@@ -593,142 +759,10 @@ LayerTreeModel::data (const QModelIndex &index, int role) const
           }
         }
 
-        unsigned int w = 32;
-        unsigned int h = 16;
-          
+        QSize is = icon_size ();
+
         if (animate_visible) {
-
-          lay::color_t def_color   = 0x808080;
-          lay::color_t fill_color  = iter->has_fill_color (true)  ? iter->eff_fill_color (true)  : def_color;
-          lay::color_t frame_color = iter->has_frame_color (true) ? iter->eff_frame_color (true) : def_color;
-
-          QImage image (w, h, QImage::Format_RGB32);
-          image.fill (m_background_color.rgb ());
-
-          //  TODO: adjust the resolution according to the oversampling mode
-          lay::Bitmap fill (w, h, 1.0);
-          lay::Bitmap frame (w, h, 1.0);
-          lay::Bitmap text (w, h, 1.0);
-          lay::Bitmap vertex (w, h, 1.0);
-
-          unsigned int mask_w      = 31;
-          unsigned int mask_all    = 0xfffffffe;
-          unsigned int mask_left   = 0x80000000;
-          unsigned int mask_right  = 0x00000002;
-          unsigned int mask_center = 0x00010000;
-
-          if (! iter->visible (true)) {
-
-            mask_w      = 8;
-            mask_all    = 0xff800000;
-            mask_left   = 0x80000000;
-            mask_right  = 0x00800000;
-            mask_center = 0x08000000;
-
-            //  Show the arrow if it is invisible also locally.
-            if (! iter->visible (false)) {
-              text.scanline (4) [0]  = 0x00008000 << 1;
-              text.scanline (5) [0]  = 0x00018000 << 1;
-              text.scanline (6) [0]  = 0x00038000 << 1;
-              text.scanline (7) [0]  = 0x00078000 << 1;
-              text.scanline (8) [0]  = 0x00038000 << 1;
-              text.scanline (9) [0]  = 0x00018000 << 1;
-              text.scanline (10) [0] = 0x00008000 << 1;
-            }
-
-          }
-
-          if (mp_view->no_stipples ()) {
-            //  Show a partial stipple pattern only for "no stipple" mode
-            for (unsigned int i = 1; i < h - 2; ++i) {
-              fill.scanline (i) [0] = 0xff800000;
-            }
-          } else {
-            for (unsigned int i = 1; i < h - 2; ++i) {
-              fill.scanline (i) [0] = mask_all;
-            }
-          }
-
-          int lw = iter->width (true);
-          if (lw < 0) {
-            //  default line width is 0 for parents and 1 for leafs
-            lw = iter->has_children () ? 0 : 1;
-          }
-
-          int p0 = lw / 2;
-          int p1 = (lw - 1) / 2;
-          if (p0 < 0) {
-            p0 = 0;
-          } else if (p0 > 7) {
-            p0 = 7;
-          }
-          if (p1 < 0) {
-            p1 = 0;
-          } else if (p1 > 7) {
-            p1 = 7;
-          }
-
-          int p0x = p0, p1x = p1;
-          unsigned int ddx = 0;
-          unsigned int ddy = h - 2 - p1 - p0;
-          if (iter->xfill (true)) {
-            ddx = mask_w - p0 - p1 - 1;
-          }
-          unsigned int d = ddx / 2;
-
-          frame.scanline (p0) [0] = mask_all << p1;
-          for (unsigned int i = p0; i < h - 2; ++i) {
-            frame.scanline (i) [0] |= (mask_left >> p0) | (mask_right << p1);
-            frame.scanline (i) [0] |= (mask_left >> p0x) | (mask_right << p1x);
-            while (d < ddx) {
-              d += ddy;
-              frame.scanline (i) [0] |= (mask_left >> p0x) | (mask_right << p1x);
-              ++p0x;
-              ++p1x;
-            }
-            if (d >= ddx) {
-              d -= ddx;
-            }
-          }
-          frame.scanline (h - 2 - p1) [0] = mask_all << p1;
-
-          if (! iter->valid (true)) {
-
-            text.scanline (4) [0]  |= 0x00000c60;
-            text.scanline (5) [0]  |= 0x00000ee0;
-            text.scanline (6) [0]  |= 0x000007c0;
-            text.scanline (7) [0]  |= 0x00000380;
-            text.scanline (8) [0]  |= 0x000007c0;
-            text.scanline (9) [0]  |= 0x00000ee0;
-            text.scanline (10) [0] |= 0x00000c60;
-
-            for (unsigned int i = 3; i < 12; ++i) {
-              fill.scanline (i) [0] &= ~0x00001ff0;
-              frame.scanline (i) [0] &= ~0x00001ff0;
-            }
-
-          }
-
-          vertex.scanline (h / 2 - 1) [0] = mask_center;
-
-          lay::ViewOp::Mode mode = lay::ViewOp::Copy;
-
-          //  create fill 
-          single_bitmap_to_image (lay::ViewOp (fill_color, mode, 0, iter->eff_dither_pattern (true), di_off), fill, &image, mp_view->dither_pattern (), mp_view->line_styles (), w, h);
-          //  create frame 
-          if (lw == 0) {
-            single_bitmap_to_image (lay::ViewOp (frame_color, mode, 0 /*solid line*/, 2 /*dotted*/, 0), frame, &image, mp_view->dither_pattern (), mp_view->line_styles (), w, h);
-          } else {
-            single_bitmap_to_image (lay::ViewOp (frame_color, mode, iter->eff_line_style (true), 0, 0, lay::ViewOp::Rect, lw), frame, &image, mp_view->dither_pattern (), mp_view->line_styles (), w, h);
-          }
-          //  create text 
-          single_bitmap_to_image (lay::ViewOp (frame_color, mode, 0, 0, 0), text, &image, mp_view->dither_pattern (), mp_view->line_styles (), w, h);
-          //  create vertex 
-          single_bitmap_to_image (lay::ViewOp (frame_color, mode, 0, 0, 0, lay::ViewOp::Cross, iter->marked (true) ? 9/*mark size*/ : 0), vertex, &image, mp_view->dither_pattern (),mp_view->line_styles (),  w, h);
-
-          QPixmap pixmap = QPixmap::fromImage (image); // Qt 4.6.0 workaround
-          return QVariant (QIcon (pixmap));
-
+          return QVariant (icon_for_layer (iter, mp_view, is.width (), is.height (), di_off));
         } else {
           return QVariant (QIcon ());
         }
diff --git a/src/laybasic/laybasic/layLayerTreeModel.h b/src/laybasic/laybasic/layLayerTreeModel.h
index b52d7cdaf..852184ab1 100644
--- a/src/laybasic/laybasic/layLayerTreeModel.h
+++ b/src/laybasic/laybasic/layLayerTreeModel.h
@@ -104,6 +104,16 @@ public:
   virtual QModelIndex index (int row, int column, const QModelIndex &parent) const;
   virtual QModelIndex parent (const QModelIndex &index) const;
 
+  /**
+   *  @brief Provides an icon for a given layer style
+   */
+  static QIcon icon_for_layer (const lay::LayerPropertiesConstIterator &iter, lay::LayoutView *view, unsigned int w, unsigned int h, unsigned int di_offset, bool no_state = false);
+
+  /**
+   *  @brief Gets the preferred icon size
+   */
+  QSize icon_size () const;
+
   /**
    *  @brief Convert a lay::LayerPropertiesConstIterator to a QModelIndex
    */
diff --git a/src/laybasic/laybasic/layLayoutView.cc b/src/laybasic/laybasic/layLayoutView.cc
index f7ae519f5..fe3c642b7 100644
--- a/src/laybasic/laybasic/layLayoutView.cc
+++ b/src/laybasic/laybasic/layLayoutView.cc
@@ -46,14 +46,12 @@
 #include "layLayoutView.h"
 #include "layViewOp.h"
 #include "layViewObject.h"
-#include "layLayoutViewConfigPages.h"
 #include "laybasicConfig.h"
 #include "layConverters.h"
 #include "layGridNet.h"
 #include "layMove.h"
 #include "layZoomBox.h"
 #include "layMouseTracker.h"
-#include "layTipDialog.h"
 #include "layEditable.h"
 #include "layFixedFont.h"
 #include "laySelector.h"
@@ -68,16 +66,12 @@
 #include "layBookmarkManagementForm.h"
 #include "layNetlistBrowserDialog.h"
 #include "layBookmarksView.h"
-#include "laySelectCellViewForm.h"
-#include "layCellSelectionForm.h"
-#include "layLayoutPropertiesForm.h"
-#include "layLayoutStatisticsForm.h"
+#include "layEditorOptionsFrame.h"
+#include "layEditorOptionsPages.h"
 #include "dbClipboard.h"
 #include "dbLayout.h"
 #include "dbLayoutUtils.h"
-#include "dbRecursiveShapeIterator.h"
 #include "dbManager.h"
-#include "dbEdgeProcessor.h"
 #include "dbLibrary.h"
 #include "rdb.h"
 #include "rdbMarkerBrowserDialog.h"
@@ -262,7 +256,8 @@ LayoutView::LayoutView (db::Manager *manager, bool editable, lay::Plugin *plugin
     m_editable (editable),
     m_options (options),
     m_annotation_shapes (manager),
-    dm_prop_changed (this, &LayoutView::do_prop_changed) 
+    dm_prop_changed (this, &LayoutView::do_prop_changed),
+    dm_setup_editor_option_pages (this, &LayoutView::do_setup_editor_options_pages)
 {
   //  either it's us or the parent has a dispatcher
   tl_assert (dispatcher () != 0);
@@ -280,7 +275,8 @@ LayoutView::LayoutView (lay::LayoutView *source, db::Manager *manager, bool edit
     m_editable (editable),
     m_options (options),
     m_annotation_shapes (manager),
-    dm_prop_changed (this, &LayoutView::do_prop_changed)
+    dm_prop_changed (this, &LayoutView::do_prop_changed),
+    dm_setup_editor_option_pages (this, &LayoutView::do_setup_editor_options_pages)
 {
   //  either it's us or the parent has a dispatcher
   tl_assert (dispatcher () != 0);
@@ -398,6 +394,7 @@ LayoutView::init (db::Manager *mgr, QWidget * /*parent*/)
   mp_libraries_view = 0;
   mp_bookmarks_view = 0;
   mp_libraries_frame = 0;
+  mp_editor_options_frame = 0;
   mp_bookmarks_frame = 0;
   mp_min_hier_spbx = 0;
   mp_max_hier_spbx = 0;
@@ -460,20 +457,10 @@ LayoutView::init (db::Manager *mgr, QWidget * /*parent*/)
   m_marker_halo = true;
   m_transient_selection_mode = true;
   m_sel_inside_pcells = false;
-  m_move_to_origin_mode_x = 0;
-  m_move_to_origin_mode_y = 0;
-  m_del_cell_mode = 0;
-  m_layer_hier_mode = 0;
   m_add_other_layers = false;
   m_always_show_source = false;
   m_always_show_ld = true;
   m_always_show_layout_index = false;
-  m_duplicate_hier_mode = 2;
-  m_clear_before = true;
-  m_copy_cva = -1;
-  m_copy_cvr = -1;
-  m_copy_layera = -1;
-  m_copy_layerr = -1;
   m_search_range = 5;
 
   m_layer_properties_lists.push_back (new LayerPropertiesList ());
@@ -560,14 +547,13 @@ LayoutView::init (db::Manager *mgr, QWidget * /*parent*/)
 
   if ((m_options & LV_NoLibrariesView) == 0 && (m_options & LV_Naked) == 0) {
 
-    QFrame *libraries_frame = new QFrame (0);
-    libraries_frame->setObjectName (QString::fromUtf8 ("libs_frame"));
-    mp_libraries_frame = libraries_frame;
-    QVBoxLayout *left_frame_ly = new QVBoxLayout (libraries_frame);
+    mp_libraries_frame = new QFrame (0);
+    mp_libraries_frame->setObjectName (QString::fromUtf8 ("libs_frame"));
+    QVBoxLayout *left_frame_ly = new QVBoxLayout (mp_libraries_frame);
     left_frame_ly->setMargin (0);
     left_frame_ly->setSpacing (0);
 
-    mp_libraries_view = new lay::LibrariesView (this, libraries_frame, "libs");
+    mp_libraries_view = new lay::LibrariesView (this, mp_libraries_frame, "libs");
     left_frame_ly->addWidget (mp_libraries_view, 1 /*stretch*/);
 
     connect (mp_libraries_view, SIGNAL (active_library_changed (int)), this, SLOT (active_library_changed (int)));
@@ -575,6 +561,15 @@ LayoutView::init (db::Manager *mgr, QWidget * /*parent*/)
 
   }
 
+  if ((m_options & LV_NoEditorOptionsPanel) == 0 && (m_options & LV_Naked) == 0) {
+
+    mp_editor_options_frame = new lay::EditorOptionsFrame (0);
+    mp_editor_options_frame->populate (this);
+
+    connect (mp_editor_options_frame, SIGNAL (destroyed ()), this, SLOT (side_panel_destroyed ()));
+
+  }
+
   //  occupy services and editables:
   //  these services get deleted by the canvas destructor automatically:
   if ((m_options & LV_NoTracker) == 0) {
@@ -598,6 +593,7 @@ LayoutView::init (db::Manager *mgr, QWidget * /*parent*/)
     connect (mp_control_frame, SIGNAL (destroyed ()), this, SLOT (side_panel_destroyed ()));
     connect (mp_control_panel, SIGNAL (tab_changed ()), this, SLOT (layer_tab_changed ()));
     connect (mp_control_panel, SIGNAL (order_changed ()), this, SLOT (layer_order_changed ()));
+    connect (mp_control_panel, SIGNAL (current_layer_changed (const lay::LayerPropertiesConstIterator &)), this, SLOT (current_layer_changed_slot (const lay::LayerPropertiesConstIterator &)));
     /*
     connect (mp_control_panel, SIGNAL (marked_changed ()), this, SLOT (prop_changed ()));
     connect (mp_control_panel, SIGNAL (width_changed ()), this, SLOT (prop_changed ()));
@@ -616,9 +612,6 @@ LayoutView::init (db::Manager *mgr, QWidget * /*parent*/)
 
   create_plugins ();
 
-  m_new_layer_props.layer = 1;
-  m_new_layer_props.datatype = 0;
-
   config_setup ();
 }
 
@@ -707,6 +700,11 @@ LayoutView::~LayoutView ()
   mp_libraries_frame = 0;
   mp_libraries_view = 0;
 
+  if (mp_editor_options_frame) {
+    delete mp_editor_options_frame;
+  }
+  mp_editor_options_frame = 0;
+
   if (mp_bookmarks_frame) {
     delete mp_bookmarks_frame;
   }
@@ -719,6 +717,26 @@ QWidget *LayoutView::menu_parent_widget ()
   return this;
 }
 
+lay::EditorOptionsPages *LayoutView::editor_options_pages ()
+{
+  if (! mp_editor_options_frame) {
+    return 0;
+  } else {
+    return mp_editor_options_frame->pages_widget ();
+  }
+}
+
+void LayoutView::do_setup_editor_options_pages ()
+{
+  //  intialize the editor option pages
+  lay::EditorOptionsPages *eo_pages = editor_options_pages ();
+  if (eo_pages) {
+    for (std::vector<lay::EditorOptionsPage *>::const_iterator op = eo_pages->pages ().begin (); op != eo_pages->pages ().end (); ++op) {
+      (*op)->setup (this);
+    }
+  }
+}
+
 void LayoutView::side_panel_destroyed ()
 {
   if (sender () == mp_control_frame) {
@@ -730,6 +748,8 @@ void LayoutView::side_panel_destroyed ()
   } else if (sender () == mp_libraries_frame) {
     mp_libraries_frame = 0;
     mp_libraries_view = 0;
+  } else if (sender () == mp_editor_options_frame) {
+    mp_editor_options_frame = 0;
   } else if (sender () == mp_bookmarks_frame) {
     mp_bookmarks_frame = 0;
     mp_bookmarks_view = 0;
@@ -868,6 +888,8 @@ void LayoutView::create_plugins (const lay::PluginDeclaration *except_this)
 
   }
 
+  dm_setup_editor_option_pages ();
+
   mode (default_mode ());
 }
 
@@ -1645,6 +1667,14 @@ LayoutView::configure (const std::string &name, const std::string &value)
   }
 }
 
+void
+LayoutView::config_finalize ()
+{
+  //  It's important that the editor option pages are updated last - because the
+  //  configuration change may trigger other configuration changes
+  dm_setup_editor_option_pages ();
+}
+
 void 
 LayoutView::enable_edits (bool enable)
 {
@@ -1679,7 +1709,41 @@ LayoutView::enable_edits (bool enable)
   }
 }
 
-void 
+bool
+LayoutView::set_or_request_current_layer (unsigned int cv_index, const db::LayerProperties &lp)
+{
+  bool ok = set_current_layer (cv_index, lp);
+  if (ok) {
+    return true;
+  }
+
+  if (! mp_control_panel) {
+    return false;
+  }
+
+  const lay::CellView &cv = cellview (cv_index);
+  if (! cv.is_valid ()) {
+    return false;
+  }
+
+  if (QMessageBox::question (this, tr ("Create Layer"), tr ("Layer %1 does not exist yet. Create it now?").arg (tl::to_qstring (lp.to_string ()))) == QMessageBox::Yes) {
+
+    lay::LayerPropertiesNode lpn;
+    lpn.set_source (lay::ParsedLayerSource (lp, cv_index));
+    init_layer_properties (lpn);
+
+    transaction (tl::to_string (QObject::tr ("Create new layer")));
+    set_current_layer (lay::LayerPropertiesConstIterator (& insert_layer (end_layers (), lpn)));
+    commit ();
+
+    return true;
+
+  }
+
+  return false;
+}
+
+bool
 LayoutView::set_current_layer (unsigned int cv_index, const db::LayerProperties &lp) 
 {
   //  rename the ones that got shifted.
@@ -1687,13 +1751,14 @@ LayoutView::set_current_layer (unsigned int cv_index, const db::LayerProperties
   while (! l.at_end ()) {
     if (l->source (true).cv_index () == int (cv_index) && l->source (true).layer_props ().log_equal (lp)) {
       set_current_layer (l);
-      break;
+      return true;
     }
     ++l;
   }
+  return false;
 }
 
-void 
+void
 LayoutView::set_current_layer (const lay::LayerPropertiesConstIterator &l) 
 {
   if (mp_control_panel) {
@@ -5272,923 +5337,6 @@ LayoutView::cut ()
   }
 }
 
-void 
-LayoutView::cm_align_cell_origin ()
-{
-  int cv_index = active_cellview_index ();
-  if (cv_index >= 0) {
-
-    const db::Cell *cell = cellview (cv_index).cell ();
-    if (! cell) {
-      return;
-    }
-    if (cell->is_proxy ()) {
-      throw tl::Exception (tl::to_string (QObject::tr ("Cannot use this function on a PCell or library cell")));
-    }
-
-    lay::AlignCellOptionsDialog dialog (this);
-    if (dialog.exec_dialog (m_align_cell_options)) {
-
-      clear_selection ();
-
-      transaction (tl::to_string (QObject::tr ("Align cell origin")));
-
-      db::Box bbox; 
-
-      if (m_align_cell_options.visible_only) {
-        for (lay::LayerPropertiesConstIterator l = begin_layers (); !l.at_end (); ++l) {
-          if (! l->has_children () && l->layer_index () >= 0 && l->cellview_index () == cv_index && l->visible (true /*real*/)) {
-            bbox += cell->bbox (l->layer_index ());
-          }
-        }
-      } else {
-        bbox = cell->bbox ();
-      }
-
-      db::Coord refx, refy;
-      switch (m_align_cell_options.mode_x) {
-      case -1:
-        refx = bbox.left ();
-        break;
-      case 1:
-        refx = bbox.right ();
-        break;
-      default:
-        refx = bbox.center ().x ();
-        break;
-      }
-      switch (m_align_cell_options.mode_y) {
-      case -1:
-        refy = bbox.bottom ();
-        break;
-      case 1:
-        refy = bbox.top ();
-        break;
-      default:
-        refy = bbox.center ().y ();
-        break;
-      }
-
-      db::Layout &layout = cellview (cv_index)->layout ();
-      db::Cell &nc_cell = layout.cell (cell->cell_index ());
-
-      db::Trans t (db::Vector (-refx + db::coord_traits<db::Coord>::rounded (m_align_cell_options.xpos / layout.dbu ()), -refy + db::coord_traits<db::Coord>::rounded (m_align_cell_options.ypos / layout.dbu ())));
-
-      for (unsigned int i = 0; i < layout.layers (); ++i) {
-        if (layout.is_valid_layer (i)) {
-          db::Shapes &shapes = nc_cell.shapes (i);
-          for (db::Shapes::shape_iterator s = shapes.begin (db::ShapeIterator::All); ! s.at_end (); ++s) {
-            shapes.transform (*s, t);
-          }
-        }
-      }
-
-      for (db::Cell::const_iterator inst = nc_cell.begin (); ! inst.at_end (); ++inst) {
-        nc_cell.transform (*inst, t);
-      }
-
-      if (m_align_cell_options.adjust_parents) {
-
-        std::vector<std::pair<db::Cell *, db::Instance> > insts_to_modify;
-        for (db::Cell::parent_inst_iterator pi = nc_cell.begin_parent_insts (); ! pi.at_end (); ++pi) {
-          insts_to_modify.push_back (std::make_pair (& layout.cell (pi->parent_cell_index ()), pi->child_inst ()));
-        }
-
-        db::Trans ti (db::Vector (refx, refy));
-        for (std::vector<std::pair<db::Cell *, db::Instance> >::const_iterator im = insts_to_modify.begin (); im != insts_to_modify.end (); ++im) {
-          im->first->transform (im->second, db::Trans (db::Vector (im->second.complex_trans ().trans (db::Vector (refx, refy)))));
-        }
-
-      }
-
-      commit ();
-
-    }
-
-  }
-}
-
-void
-LayoutView::cm_cell_user_properties ()
-{
-  if (! mp_hierarchy_panel) {
-    return;
-  }
-
-  int cv_index = active_cellview_index ();
-  cell_path_type path;
-  mp_hierarchy_panel->current_cell (cv_index, path);
-
-  if (cv_index >= 0 && path.size () > 0) {
-
-    db::Layout &layout = cellview (cv_index)->layout ();
-    db::Cell &cell = layout.cell (path.back ());
-    db::properties_id_type prop_id = cell.prop_id ();
-
-    lay::UserPropertiesForm props_form (this);
-    if (props_form.show (this, cv_index, prop_id)) {
-
-      transaction (tl::to_string (QObject::tr ("Edit cell's user propertes")));
-      cell.prop_id (prop_id);
-      commit ();
-
-    }
-
-  }
-}
-
-void
-LayoutView::cm_cell_replace ()
-{
-  if (! mp_hierarchy_panel) {
-    return;
-  }
-
-  int cv_index = active_cellview_index ();
-  std::vector<cell_path_type> paths;
-  mp_hierarchy_panel->selected_cells (cv_index, paths);
-
-  if (cv_index >= 0 && paths.size () > 0) {
-
-    if (paths.size () > 1) {
-      throw tl::Exception (tl::to_string (QObject::tr ("Replace cell cannot be used when multiple cells are selected")));
-    }
-
-    db::Layout &layout = cellview (cv_index)->layout ();
-
-    bool needs_to_ask = false;
-    for (std::vector<cell_path_type>::const_iterator p = paths.begin (); p != paths.end () && ! needs_to_ask; ++p) {
-      if (layout.is_valid_cell_index (p->back ()) && ! layout.cell (p->back ()).is_leaf ()) {
-        needs_to_ask = true;
-      }
-    }
-
-
-    lay::ReplaceCellOptionsDialog mode_dialog (this);
-
-    db::cell_index_type with_cell = paths.front ().back ();
-    int mode = needs_to_ask ? m_del_cell_mode : 0;
-
-    if (mode_dialog.exec_dialog (cellview (cv_index), mode, with_cell)) {
-
-      if (needs_to_ask) {
-        m_del_cell_mode = mode;
-      }
-
-      if (with_cell != paths.front ().back ()) {
-
-        //  remember the current path
-        cell_path_type cell_path (cellview (cv_index).combined_unspecific_path ());
-
-        clear_selection ();
-
-        transaction (tl::to_string (QObject::tr ("Replace cells")));
-
-        //  replace instances of the target cell with the new cell 
-
-        db::Cell &target_cell = layout.cell (paths.front ().back ());
-
-        std::vector<std::pair<db::cell_index_type, db::Instance> > parents;
-        for (db::Cell::parent_inst_iterator pi = target_cell.begin_parent_insts (); ! pi.at_end (); ++pi) {
-          parents.push_back (std::make_pair (pi->parent_cell_index (), pi->child_inst ()));
-        }
-
-        for (std::vector<std::pair<db::cell_index_type, db::Instance> >::const_iterator p = parents.begin (); p != parents.end (); ++p) {
-          db::CellInstArray ia = p->second.cell_inst ();
-          ia.object ().cell_index (with_cell);
-          layout.cell (p->first).replace (p->second, ia);
-        }
-
-        std::set<db::cell_index_type> cells_to_delete;
-        for (std::vector<cell_path_type>::const_iterator p = paths.begin (); p != paths.end (); ++p) {
-          if (! p->empty () && layout.is_valid_cell_index (p->back ())) {
-            cells_to_delete.insert (p->back ());
-            if (mode == 2) {
-              layout.cell (p->back ()).collect_called_cells (cells_to_delete);
-            }
-          }
-        }
-
-        //  support a propagation use case:
-        std::set<db::cell_index_type> cells_below_replacement_cell;
-        cells_below_replacement_cell.insert (with_cell);
-        layout.cell (with_cell).collect_called_cells (cells_below_replacement_cell);
-        for (std::set<db::cell_index_type>::const_iterator c = cells_below_replacement_cell.begin (); c != cells_below_replacement_cell.end (); ++c) {
-          cells_to_delete.erase (*c);
-        }
-
-        if (mode == 0 || mode == 2) {
-          layout.delete_cells (cells_to_delete);
-        } else if (mode == 1) {
-          layout.prune_cells (cells_to_delete);
-        }
-
-        layout.cleanup ();
-
-        commit ();
-
-        //  If one of the cells in the path was deleted, establish a valid path
-
-        bool needs_update = false;
-        for (size_t i = cell_path.size (); i > 0; ) {
-          --i;
-          if (! layout.is_valid_cell_index (cell_path [i])) {
-            cell_path.erase (cell_path.begin () + i, cell_path.end ());
-            needs_update = true;
-          }
-        }
-
-        if (needs_update) {
-          select_cell (cell_path, cv_index);
-        }
-
-      }
-
-    }
-
-  }
-}
-
-void
-LayoutView::cm_lay_convert_to_static ()
-{
-  //  end move operations, cancel edit operations
-  cancel_edits ();
-  clear_selection ();
-
-  int cv_index = active_cellview_index ();
-  if (cv_index >= 0) {
-
-    db::Layout &layout = cellview (cv_index)->layout ();
-
-    transaction (tl::to_string (QObject::tr ("Convert all cells to static")));
-
-    std::vector<db::cell_index_type> cells;
-    for (db::Layout::const_iterator c = layout.begin (); c != layout.end (); ++c) {
-      cells.push_back (c->cell_index ());
-    }
-
-    std::map<db::cell_index_type, db::cell_index_type> cell_map;
-    for (std::vector<db::cell_index_type>::const_iterator c = cells.begin (); c != cells.end (); ++c) {
-      if (layout.is_valid_cell_index (*c)) {
-        db::cell_index_type new_cell = layout.convert_cell_to_static (*c);
-        if (new_cell != *c) {
-          cell_map.insert (std::make_pair (*c, new_cell));
-        }
-      }
-    }
-
-    //  rewrite instances
-    for (db::Layout::iterator c = layout.begin (); c != layout.end (); ++c) {
-      for (db::Cell::const_iterator i = c->begin (); ! i.at_end (); ++i) {
-        std::map<db::cell_index_type, db::cell_index_type>::const_iterator cm = cell_map.find (i->cell_index ());
-        if (cm != cell_map.end ()) {
-          db::CellInstArray ci = i->cell_inst ();
-          ci.object ().cell_index (cm->second);
-          c->replace (*i, ci);
-        }
-      }
-    }
-
-    layout.cleanup ();
-
-    commit ();
-
-  }
-}
-
-void
-LayoutView::cm_cell_convert_to_static ()
-{
-  if (! mp_hierarchy_panel) {
-    return;
-  }
-
-  int cv_index = active_cellview_index ();
-  std::vector<cell_path_type> paths;
-  mp_hierarchy_panel->selected_cells (cv_index, paths);
-
-  if (cv_index >= 0 && paths.size () > 0) {
-
-    db::Layout &layout = cellview (cv_index)->layout ();
-
-    //  remember the current path
-    cell_path_type cell_path (cellview (cv_index).combined_unspecific_path ());
-
-    clear_selection ();
-
-    transaction (tl::to_string (QObject::tr ("Convert cells to static")));
-
-    std::map<db::cell_index_type, db::cell_index_type> cell_map;
-
-    for (std::vector<cell_path_type>::iterator p = paths.begin (); p != paths.end (); ++p) {
-      if (! p->empty () && layout.is_valid_cell_index (p->back ())) {
-        db::cell_index_type new_cell = layout.convert_cell_to_static (p->back ());
-        if (new_cell != p->back ()) {
-          cell_map.insert (std::make_pair (p->back (), new_cell));
-          p->back () = new_cell;
-        }
-      }
-    }
-
-    //  rewrite instances
-    for (db::Layout::iterator c = layout.begin (); c != layout.end (); ++c) {
-      for (db::Cell::const_iterator i = c->begin (); ! i.at_end (); ++i) {
-        std::map<db::cell_index_type, db::cell_index_type>::const_iterator cm = cell_map.find (i->cell_index ());
-        if (cm != cell_map.end ()) {
-          db::CellInstArray ci = i->cell_inst ();
-          ci.object ().cell_index (cm->second);
-          c->replace (*i, ci);
-        }
-      }
-    }
-
-    layout.cleanup ();
-
-    commit ();
-
-    //  If one of the cells in the path was deleted, establish a valid path
-
-    bool needs_update = false;
-    for (size_t i = cell_path.size (); i > 0; ) {
-      --i;
-      if (! layout.is_valid_cell_index (cell_path [i])) {
-        cell_path.erase (cell_path.begin () + i, cell_path.end ());
-        needs_update = true;
-      }
-    }
-
-    if (needs_update) {
-      select_cell (cell_path, cv_index);
-    }
-
-  }
-}
-
-static void
-collect_cells_to_delete (const db::Layout &layout, const db::Cell &cell, std::set<db::cell_index_type> &called)
-{
-  //  don't delete proxies - they are deleted later when the layout is cleaned
-  for (db::Cell::child_cell_iterator cc = cell.begin_child_cells (); ! cc.at_end (); ++cc) {
-    if (called.find (*cc) == called.end () && !layout.cell (*cc).is_proxy ()) {
-      called.insert (*cc);
-      collect_cells_to_delete (layout, layout.cell (*cc), called);
-    }
-  }
-}
-
-void
-LayoutView::cm_cell_delete ()
-{
-  if (! mp_hierarchy_panel) {
-    return;
-  }
-
-  int cv_index = active_cellview_index ();
-  std::vector<cell_path_type> paths;
-  mp_hierarchy_panel->selected_cells (cv_index, paths);
-
-  if (cv_index >= 0 && paths.size () > 0) {
-
-    db::Layout &layout = cellview (cv_index)->layout ();
-
-    bool needs_to_ask = false;
-    for (std::vector<cell_path_type>::const_iterator p = paths.begin (); p != paths.end () && ! needs_to_ask; ++p) {
-      if (layout.is_valid_cell_index (p->back ()) && ! layout.cell (p->back ()).is_leaf ()) {
-        needs_to_ask = true;
-      }
-    }
-
-    int mode = m_del_cell_mode;
-    if (! needs_to_ask) {
-      mode = 0;
-    }
-
-    lay::DeleteCellModeDialog mode_dialog (this);
-    if (! needs_to_ask || mode_dialog.exec_dialog (mode)) {
-
-      if (needs_to_ask) {
-        m_del_cell_mode = mode;
-      }
-
-      //  remember the current path
-      cell_path_type cell_path (cellview (cv_index).combined_unspecific_path ());
-
-      clear_selection ();
-
-      std::set<db::cell_index_type> cells_to_delete;
-      for (std::vector<cell_path_type>::const_iterator p = paths.begin (); p != paths.end (); ++p) {
-        if (! p->empty () && layout.is_valid_cell_index (p->back ())) {
-          cells_to_delete.insert (p->back ());
-          if (mode == 2) {
-            collect_cells_to_delete (layout, layout.cell (p->back ()), cells_to_delete);
-          }
-        }
-      }
-
-      transaction (tl::to_string (QObject::tr ("Delete cells")));
-
-      if (mode == 0 || mode == 2) {
-        layout.delete_cells (cells_to_delete);
-      } else if (mode == 1) {
-        layout.prune_cells (cells_to_delete);
-      }
-
-      layout.cleanup ();
-
-      commit ();
-
-      //  If one of the cells in the path was deleted, establish a valid path
-
-      bool needs_update = false;
-      for (size_t i = cell_path.size (); i > 0; ) {
-        --i;
-        if (! layout.is_valid_cell_index (cell_path [i])) {
-          cell_path.erase (cell_path.begin () + i, cell_path.end ());
-          needs_update = true;
-        }
-      }
-
-      if (needs_update) {
-        select_cell (cell_path, cv_index);
-      }
-
-    }
-
-  }
-}
-
-void 
-LayoutView::cm_layer_copy ()
-{
-  if (mp_control_panel) {
-    mp_control_panel->copy ();
-  }
-}
-
-void 
-LayoutView::cm_layer_cut ()
-{
-  if (mp_control_panel) {
-    db::Transaction trans (manager (), tl::to_string (QObject::tr ("Cut Layers"))); 
-    mp_control_panel->cut ();
-  }
-}
-
-void 
-LayoutView::cm_layer_paste ()
-{
-  if (mp_control_panel) {
-    db::Transaction trans (manager (), tl::to_string (QObject::tr ("Paste Layers"))); 
-    mp_control_panel->paste ();
-  }
-}
-
-void
-LayoutView::cm_cell_cut ()
-{
-  if (mp_hierarchy_panel) {
-    //  TODO: currently the hierarchy panel's cut function does it's own transaction handling.
-    //  Otherwise the cut function is not working propertly.
-    mp_hierarchy_panel->cut ();
-  }
-}
-
-void
-LayoutView::cm_cell_paste ()
-{
-  if (mp_hierarchy_panel) {
-    db::Transaction trans (manager (), tl::to_string (QObject::tr ("Paste Cells"))); 
-    mp_hierarchy_panel->paste ();
-  }
-}
-
-void
-LayoutView::cm_cell_copy ()
-{
-  if (mp_hierarchy_panel) {
-    mp_hierarchy_panel->copy ();
-  }
-}
-
-void
-LayoutView::cm_cell_flatten ()
-{
-  if (! mp_hierarchy_panel) {
-    return;
-  }
-
-  tl_assert (is_editable ());
-
-  int cv_index = active_cellview_index ();
-  if (cv_index >= 0) {
-
-    const lay::CellView &cv = cellview (cv_index);
-    if (cv.is_valid ()) {
-
-      std::vector<HierarchyControlPanel::cell_path_type> paths;
-      mp_hierarchy_panel->selected_cells (cv_index, paths);
-      if (paths.empty ()) {
-        throw tl::Exception (tl::to_string (QObject::tr ("No cells selected for flattening")));
-      }
-
-      for (std::vector<HierarchyControlPanel::cell_path_type>::const_iterator p = paths.begin (); p != paths.end (); ++p) {
-        if (p->size () > 0 && cv->layout ().cell (p->back ()).is_proxy ()) {
-          throw tl::Exception (tl::to_string (QObject::tr ("Cannot use this function on a PCell or library cell")));
-        }
-      }
-
-      FlattenInstOptionsDialog options_dialog (this);
-
-      int flatten_insts_levels = -1;
-      bool prune = true;
-      if (options_dialog.exec_dialog (flatten_insts_levels, prune) && flatten_insts_levels != 0) {
-
-        bool supports_undo = true;
-
-        if (manager () && manager ()->is_enabled ()) {
-
-          lay::TipDialog td (QApplication::activeWindow (), 
-                             tl::to_string (QObject::tr ("Undo buffering for the following operation can be memory and time consuming.\nChoose \"Yes\" to use undo buffering or \"No\" for no undo buffering. Warning: in the latter case, the undo history will be lost.\n\nChoose undo buffering?")), 
-                             "flatten-undo-buffering",
-                             lay::TipDialog::yesnocancel_buttons);
-
-          lay::TipDialog::button_type button = lay::TipDialog::null_button;
-          td.exec_dialog (button);
-          if (button == lay::TipDialog::cancel_button) {
-            return;
-          }
-
-          supports_undo = (button == lay::TipDialog::yes_button);
-
-        } else {
-          supports_undo = false;
-        }
-
-        cancel_edits ();
-        clear_selection ();
-
-        if (manager ()) {
-          if (! supports_undo) {
-            manager ()->clear ();
-          } else {
-            manager ()->transaction (tl::to_string (QObject::tr ("Flatten cell")));
-          }
-        }
-
-        db::Layout &layout = cv->layout ();
-
-        std::set<db::cell_index_type> child_cells;
-        for (std::vector<HierarchyControlPanel::cell_path_type>::const_iterator p = paths.begin (); p != paths.end (); ++p) {
-          if (p->size () > 0) {
-            layout.cell (p->back ()).collect_called_cells (child_cells);
-          }
-        }
-
-        //  don't flatten cells which are child cells of the cells to flatten
-        std::set<db::cell_index_type> cells_to_flatten;
-        for (std::vector<HierarchyControlPanel::cell_path_type>::const_iterator p = paths.begin (); p != paths.end (); ++p) {
-          if (p->size () > 0 && child_cells.find (p->back ()) == child_cells.end ()) {
-            cells_to_flatten.insert (p->back ());
-          }
-        }
-
-        for (std::set<db::cell_index_type>::const_iterator c = cells_to_flatten.begin (); c != cells_to_flatten.end (); ++c) {
-          db::Cell &target_cell = layout.cell (*c);
-          layout.flatten (target_cell, flatten_insts_levels, prune);
-        }
-
-        layout.cleanup ();
-
-        if (supports_undo && manager ()) {
-          manager ()->commit ();
-        }
-
-      }
-
-    }
-
-  }
-}
-
-void
-LayoutView::cm_cell_rename ()
-{
-  if (! mp_hierarchy_panel) {
-    return;
-  }
-
-  int cv_index = active_cellview_index ();
-  cell_path_type path;
-  mp_hierarchy_panel->current_cell (cv_index, path);
-
-  if (cv_index >= 0 && path.size () > 0) {
-
-    lay::RenameCellDialog name_dialog (this);
-
-    db::Layout &layout = cellview (cv_index)->layout ();
-    std::string name (layout.cell_name (path.back ()));
-    if (name_dialog.exec_dialog (layout, name)) {
-
-      transaction (tl::to_string (QObject::tr ("Rename cell")));
-      layout.rename_cell (path.back (), name.c_str ());
-      commit ();
-
-    }
-
-  }
-}
-
-void
-LayoutView::cm_cell_select ()
-{
-  if (mp_hierarchy_panel) {
-    mp_hierarchy_panel->cm_cell_select ();
-  }
-}
-
-void
-LayoutView::cm_open_current_cell ()
-{
-  set_current_cell_path (active_cellview_index (), cellview (active_cellview_index ()).combined_unspecific_path ());
-}
-
-void
-LayoutView::cm_cell_hide ()
-{
-  if (mp_hierarchy_panel) {
-
-    std::vector<HierarchyControlPanel::cell_path_type> paths;
-    mp_hierarchy_panel->selected_cells (active_cellview_index (), paths);
-
-    transaction (tl::to_string (QObject::tr ("Hide cell")));
-
-    for (std::vector<HierarchyControlPanel::cell_path_type>::const_iterator p = paths.begin (); p != paths.end (); ++p) {
-      if (! p->empty ()) {
-        hide_cell (p->back (), active_cellview_index ());
-      }
-    }
-
-    commit ();
-
-  }
-}
-
-void
-LayoutView::cm_cell_show ()
-{
-  if (mp_hierarchy_panel) {
-
-    std::vector<HierarchyControlPanel::cell_path_type> paths;
-    mp_hierarchy_panel->selected_cells (active_cellview_index (), paths);
-
-    transaction (tl::to_string (QObject::tr ("Show cell")));
-
-    for (std::vector<HierarchyControlPanel::cell_path_type>::const_iterator p = paths.begin (); p != paths.end (); ++p) {
-      if (! p->empty ()) {
-        show_cell (p->back (), active_cellview_index ());
-      }
-    }
-
-    commit ();
-
-  }
-}
-
-void
-LayoutView::cm_cell_show_all ()
-{
-  if (mp_hierarchy_panel) {
-    transaction (tl::to_string (QObject::tr ("Show all cells")));
-    show_all_cells ();
-    commit ();
-  }
-}
-
-void
-LayoutView::cm_select_all ()
-{
-  if (mp_control_panel) {
-    mp_control_panel->cm_select_all ();
-  }
-}
-
-void
-LayoutView::cm_new_tab ()
-{
-  if (mp_control_panel) {
-    mp_control_panel->cm_new_tab ();
-  }
-}
-
-void
-LayoutView::cm_remove_tab ()
-{
-  if (mp_control_panel) {
-    mp_control_panel->cm_remove_tab ();
-  }
-}
-
-void
-LayoutView::cm_rename_tab ()
-{
-  if (mp_control_panel) {
-    mp_control_panel->cm_rename_tab ();
-  }
-}
-
-void
-LayoutView::cm_make_invalid ()
-{
-  if (mp_control_panel) {
-    mp_control_panel->cm_make_invalid ();
-  }
-}
-
-void
-LayoutView::cm_make_valid ()
-{
-  if (mp_control_panel) {
-    mp_control_panel->cm_make_valid ();
-  }
-}
-
-void
-LayoutView::cm_hide ()
-{
-  if (mp_control_panel) {
-    mp_control_panel->cm_hide ();
-  }
-}
-
-void
-LayoutView::cm_hide_all ()
-{
-  if (mp_control_panel) {
-    mp_control_panel->cm_hide_all ();
-  }
-}
-
-void
-LayoutView::cm_show_only ()
-{
-  if (mp_control_panel) {
-    mp_control_panel->cm_show_only ();
-  }
-}
-
-void
-LayoutView::cm_show_all ()
-{
-  if (mp_control_panel) {
-    mp_control_panel->cm_show_all ();
-  }
-}
-
-void
-LayoutView::cm_show ()
-{
-  if (mp_control_panel) {
-    mp_control_panel->cm_show ();
-  }
-}
-
-void
-LayoutView::cm_rename ()
-{
-  if (mp_control_panel) {
-    mp_control_panel->cm_rename ();
-  }
-}
-
-void
-LayoutView::cm_delete ()
-{
-  if (mp_control_panel) {
-    mp_control_panel->cm_delete ();
-  }
-}
-
-void
-LayoutView::cm_insert ()
-{
-  if (mp_control_panel) {
-    mp_control_panel->cm_insert ();
-  }
-}
-
-void
-LayoutView::cm_group ()
-{
-  if (mp_control_panel) {
-    mp_control_panel->cm_group ();
-  }
-}
-
-void
-LayoutView::cm_ungroup ()
-{
-  if (mp_control_panel) {
-    mp_control_panel->cm_ungroup ();
-  }
-}
-
-void
-LayoutView::cm_source ()
-{
-  if (mp_control_panel) {
-    mp_control_panel->cm_source ();
-  }
-}
-
-void
-LayoutView::cm_sort_by_name ()
-{
-  if (mp_control_panel) {
-    mp_control_panel->cm_sort_by_name ();
-  }
-}
-
-void
-LayoutView::cm_sort_by_ild ()
-{
-  if (mp_control_panel) {
-    mp_control_panel->cm_sort_by_ild ();
-  }
-}
-
-void
-LayoutView::cm_sort_by_idl ()
-{
-  if (mp_control_panel) {
-    mp_control_panel->cm_sort_by_idl ();
-  }
-}
-
-void
-LayoutView::cm_sort_by_ldi ()
-{
-  if (mp_control_panel) {
-    mp_control_panel->cm_sort_by_ldi ();
-  }
-}
-
-void
-LayoutView::cm_sort_by_dli ()
-{
-  if (mp_control_panel) {
-    mp_control_panel->cm_sort_by_dli ();
-  }
-}
-
-void
-LayoutView::cm_regroup_by_index ()
-{
-  if (mp_control_panel) {
-    mp_control_panel->cm_regroup_by_index ();
-  }
-}
-
-void
-LayoutView::cm_regroup_by_datatype ()
-{
-  if (mp_control_panel) {
-    mp_control_panel->cm_regroup_by_datatype ();
-  }
-}
-
-void
-LayoutView::cm_regroup_by_layer ()
-{
-  if (mp_control_panel) {
-    mp_control_panel->cm_regroup_by_layer ();
-  }
-}
-
-void
-LayoutView::cm_regroup_flatten ()
-{
-  if (mp_control_panel) {
-    mp_control_panel->cm_regroup_flatten ();
-  }
-}
-
-void
-LayoutView::cm_expand_all ()
-{
-  if (mp_control_panel) {
-    mp_control_panel->cm_expand_all ();
-  }
-}
-
-void
-LayoutView::cm_add_missing ()
-{
-  if (mp_control_panel) {
-    mp_control_panel->cm_add_missing ();
-  }
-}
-
 void 
 LayoutView::add_missing_layers ()
 {
@@ -6240,6 +5388,12 @@ LayoutView::layer_snapshot () const
   return state;
 }
 
+void
+LayoutView::current_layer_changed_slot (const lay::LayerPropertiesConstIterator &iter)
+{
+  current_layer_changed_event (iter);
+}
+
 void 
 LayoutView::add_new_layers (const LayerState &state)
 {
@@ -6277,12 +5431,6 @@ LayoutView::add_new_layers (const LayerState &state)
   }
 }
 
-void
-LayoutView::cm_remove_unused ()
-{
-  remove_unused_layers ();
-}
-
 void 
 LayoutView::remove_unused_layers ()
 {
@@ -6442,11 +5590,13 @@ LayoutView::mode (int m)
   if (m != m_mode) {
 
     m_mode = m;
+    lay::Plugin *active_plugin = 0;
 
     if (m > 0) {
 
       for (std::vector<lay::Plugin *>::iterator p = mp_plugins.begin (); p != mp_plugins.end (); ++p) {
         if ((*p)->plugin_declaration ()->id () == m) {
+          active_plugin = *p;
           mp_canvas->activate ((*p)->view_service_interface ());
           break;
         }
@@ -6458,6 +5608,22 @@ LayoutView::mode (int m)
       mp_canvas->activate (mp_move_service);
     }
 
+    lay::EditorOptionsPages *eo_pages = editor_options_pages ();
+    if (eo_pages) {
+
+      //  TODO: this is very inefficient as each "activate" will regenerate the tabs
+      for (std::vector<lay::EditorOptionsPage *>::const_iterator op = eo_pages->pages ().begin (); op != eo_pages->pages ().end (); ++op) {
+        bool is_active = false;
+        if ((*op)->plugin_declaration () == 0) {
+          is_active = true;
+        } else if (active_plugin && active_plugin->plugin_declaration () == (*op)->plugin_declaration ()) {
+          is_active = true;
+        }
+        (*op)->activate (is_active);
+      }
+
+    }
+
   }
 }
 
@@ -6489,138 +5655,6 @@ LayoutView::default_mode ()
   return 0; // TODO: any generic scheme? is select, should be ruler..
 }
 
-void
-LayoutView::do_cm_duplicate (bool interactive)
-{
-  //  Do duplicate simply by concatenating copy & paste currently.
-  //  Save the clipboard state before in order to preserve the current content
-  db::Clipboard saved_clipboard;
-  db::Clipboard::instance ().swap (saved_clipboard);
-
-  try {
-    copy ();
-    clear_selection ();
-    cancel ();
-    if (interactive) {
-      paste_interactive ();
-    } else {
-      paste ();
-    }
-    db::Clipboard::instance ().swap (saved_clipboard);
-  } catch (...) {
-    db::Clipboard::instance ().swap (saved_clipboard);
-    throw;
-  }
-}
-
-void
-LayoutView::do_cm_paste (bool interactive)
-{
-  if (! db::Clipboard::instance ().empty ()) {
-    cancel ();
-    clear_selection ();
-    if (interactive) {
-      paste_interactive ();
-    } else {
-      paste ();
-    }
-  }
-}
-
-void
-LayoutView::cm_new_cell ()
-{
-  static double s_new_cell_window_size = 2.0;
-  static std::string s_new_cell_cell_name;
-
-  NewCellPropertiesDialog cell_prop_dia (this);
-  if (cell_prop_dia.exec_dialog (& cellview (active_cellview_index ())->layout (), s_new_cell_cell_name, s_new_cell_window_size)) {
-
-    db::cell_index_type new_ci = new_cell (active_cellview_index (), s_new_cell_cell_name.c_str ());
-    select_cell (new_ci, active_cellview_index ());
-
-    db::DBox zb = db::DBox (-0.5 * s_new_cell_window_size, -0.5 * s_new_cell_window_size, 0.5 * s_new_cell_window_size, 0.5 * s_new_cell_window_size);
-    if (get_max_hier_levels () < 1 || get_min_hier_levels () > 0) {
-      zoom_box_and_set_hier_levels (zb, std::make_pair (0, 1));
-    } else {
-      zoom_box (zb);
-    }
-
-  }
-}
-
-//  TODO: this constant is defined in MainWindow.cc too ...
-const int max_dirty_files = 15;
-
-void
-LayoutView::cm_reload ()
-{
-  std::vector <int> selected;
-
-  if (cellviews () > 1) {
-
-    SelectCellViewForm form (0, this, tl::to_string (QObject::tr ("Select Layouts To Reload")));
-    form.select_all ();
-
-    if (form.exec () == QDialog::Accepted) {
-      selected = form.selected_cellviews ();
-    }
-
-  } else if (cellviews () > 0) {
-    selected.push_back (0);
-  }
-
-  if (selected.size () > 0) {
-
-    int dirty_layouts = 0;
-    std::string dirty_files;
-
-    for (std::vector <int>::const_iterator i = selected.begin (); i != selected.end (); ++i) {
-
-      const lay::CellView &cv = cellview (*i);
-
-      if (cv->layout ().is_editable () && cv->is_dirty ()) {
-        ++dirty_layouts;
-        if (dirty_layouts == max_dirty_files) {
-          dirty_files += "\n...";
-        } else if (dirty_layouts < max_dirty_files) {
-          if (! dirty_files.empty ()) {
-            dirty_files += "\n";
-          }
-          dirty_files += cv->name ();
-        }
-      }
-
-    }
-
-    bool can_reload = true;
-    if (dirty_layouts != 0) {
-
-      QMessageBox mbox (this);
-      mbox.setText (tl::to_qstring (tl::to_string (QObject::tr ("The following layouts need saving:\n\n")) + dirty_files + "\n\nPress 'Reload Without Saving' to reload anyhow and discard changes."));
-      mbox.setWindowTitle (QObject::tr ("Save Needed"));
-      mbox.setIcon (QMessageBox::Warning);
-      QAbstractButton *yes_button = mbox.addButton (QObject::tr ("Reload Without Saving"), QMessageBox::YesRole);
-      mbox.addButton (QMessageBox::Cancel);
-
-      mbox.exec ();
-
-      can_reload = (mbox.clickedButton() == yes_button);
-
-    }
-
-    if (can_reload) {
-
-      //  Actually reload
-      for (std::vector <int>::const_iterator i = selected.begin (); i != selected.end (); ++i) {
-        reload_layout (*i);
-      }
-
-    }
-
-  }
-}
-
 std::vector<std::string>
 LayoutView::menu_symbols ()
 {
@@ -6640,309 +5674,9 @@ LayoutView::menu_activated (const std::string &symbol)
     }
   }
 
-  if (symbol == "cm_show_properties") {
-    show_properties (this);
-  } else if (symbol == "cm_delete") {
-
-    del ();
-    //  because a "delete" might involve objects currently edited, we cancel the edit after we have deleted the object
-    cancel ();
-    clear_selection ();
-
-  } else if (symbol == "cm_unselect_all") {
-    select (db::DBox (), lay::Editable::Reset);
-  } else if (symbol == "cm_select_all") {
-    select (full_box (), lay::Editable::Replace);
-  } else if (symbol == "cm_lv_paste") {
-    cm_layer_paste ();
-  } else if (symbol == "cm_lv_cut") {
-    cm_layer_cut ();
-  } else if (symbol == "cm_lv_copy") {
-    cm_layer_copy ();
-  } else if (symbol == "cm_cell_paste") {
-    cm_cell_paste ();
-  } else if (symbol == "cm_cell_cut") {
-    cm_cell_cut ();
-  } else if (symbol == "cm_cell_copy") {
-    cm_cell_copy ();
-  } else if (symbol == "cm_duplicate") {
-    do_cm_duplicate (false);
-  } else if (symbol == "cm_duplicate_interactive") {
-    do_cm_duplicate (true);
-  } else if (symbol == "cm_copy") {
-
-    copy ();
-    clear_selection ();
-
-  } else if (symbol == "cm_paste") {
-    do_cm_paste (false);
-  } else if (symbol == "cm_paste_interactive") {
-    do_cm_paste (true);
-  } else if (symbol == "cm_cut") {
-
-    cut ();
-    cancel (); //  see del() for reason why cancel is after cut
-    clear_selection ();
-
-  } else if (symbol == "cm_zoom_fit_sel") {
-    zoom_fit_sel ();
-  } else if (symbol == "cm_zoom_fit") {
-    zoom_fit ();
-  } else if (symbol == "cm_pan_left") {
-    pan_left ();
-  } else if (symbol == "cm_pan_right") {
-    pan_right ();
-  } else if (symbol == "cm_pan_up") {
-    pan_up ();
-  } else if (symbol == "cm_pan_down") {
-    pan_down ();
-  } else if (symbol == "cm_zoom_in") {
-    zoom_in ();
-  } else if (symbol == "cm_zoom_out") {
-    zoom_out ();
-  } else if (symbol == "cm_select_current_cell") {
-
-    if (active_cellview_index () >= 0) {
-      lay::LayoutView::cell_path_type path;
-      int cvi = active_cellview_index ();
-      current_cell_path (path);
-      select_cell_fit (path, cvi);
-    }
-
-  } else if (symbol == "cm_open_current_cell") {
-
-    if (active_cellview_index () >= 0) {
-      cm_open_current_cell ();
-    }
-
-  } else if (symbol == "cm_select_cell") {
-
-    if (active_cellview_index () >= 0) {
-
-      CellSelectionForm form (0, this, "cell_selection_form");
-
-      if (form.exec () == QDialog::Accepted &&
-          form.selected_cellview_index () >= 0) {
-        select_cell (form.selected_cellview ().combined_unspecific_path (), form.selected_cellview_index ());
-        set_current_cell_path (form.selected_cellview_index (), form.selected_cellview ().combined_unspecific_path ());
-        zoom_fit ();
-      }
-
-    }
-
-  } else if (symbol == "cm_new_cell") {
-    cm_new_cell ();
-  } else if (symbol == "cm_adjust_origin") {
-    if (active_cellview_index () >= 0) {
-      cm_align_cell_origin ();
-    }
-  } else if (symbol == "cm_cell_convert_to_static") {
-    if (active_cellview_index () >= 0) {
-      cm_cell_convert_to_static ();
-    }
-  } else if (symbol == "cm_lay_convert_to_static") {
-    if (active_cellview_index () >= 0) {
-      cm_lay_convert_to_static ();
-    }
-  } else if (symbol == "cm_lay_move") {
-    if (active_cellview_index () >= 0) {
-      cm_lay_move ();
-    }
-  } else if (symbol == "cm_lay_scale") {
-    if (active_cellview_index () >= 0) {
-      cm_lay_scale ();
-    }
-  } else if (symbol == "cm_lay_free_rot") {
-    if (active_cellview_index () >= 0) {
-      cm_lay_free_rot ();
-    }
-  } else if (symbol == "cm_lay_rot_ccw") {
-    if (active_cellview_index () >= 0) {
-      cm_lay_rot_ccw ();
-    }
-  } else if (symbol == "cm_lay_rot_cw") {
-    if (active_cellview_index () >= 0) {
-      cm_lay_rot_cw ();
-    }
-  } else if (symbol == "cm_lay_flip_y") {
-    if (active_cellview_index () >= 0) {
-      cm_lay_flip_y ();
-    }
-  } else if (symbol == "cm_lay_flip_x") {
-    if (active_cellview_index () >= 0) {
-      cm_lay_flip_x ();
-    }
-  } else if (symbol == "cm_sel_move") {
-    if (active_cellview_index () >= 0) {
-      cm_sel_move ();
-    }
-  } else if (symbol == "cm_sel_move_to") {
-    if (active_cellview_index () >= 0) {
-      cm_sel_move_to ();
-    }
-  } else if (symbol == "cm_sel_move_interactive") {
-    if (active_cellview_index () >= 0) {
-      cm_sel_move_interactive ();
-    }
-  } else if (symbol == "cm_sel_scale") {
-    if (active_cellview_index () >= 0) {
-      cm_sel_scale ();
-    }
-  } else if (symbol == "cm_sel_free_rot") {
-    if (active_cellview_index () >= 0) {
-      cm_sel_free_rot ();
-    }
-  } else if (symbol == "cm_sel_rot_ccw") {
-    if (active_cellview_index () >= 0) {
-      cm_sel_rot_ccw ();
-    }
-  } else if (symbol == "cm_sel_rot_cw") {
-    if (active_cellview_index () >= 0) {
-      cm_sel_rot_cw ();
-    }
-  } else if (symbol == "cm_sel_flip_y") {
-    if (active_cellview_index () >= 0) {
-      cm_sel_flip_y ();
-    }
-  } else if (symbol == "cm_sel_flip_x") {
-    if (active_cellview_index () >= 0) {
-      cm_sel_flip_x ();
-    }
-  } else if (symbol == "cm_edit_layer") {
-    if (active_cellview_index () >= 0) {
-      cm_edit_layer ();
-    }
-  } else if (symbol == "cm_delete_layer") {
-    if (active_cellview_index () >= 0) {
-      cm_delete_layer ();
-    }
-  } else if (symbol == "cm_clear_layer") {
-    if (active_cellview_index () >= 0) {
-      cm_clear_layer ();
-    }
-  } else if (symbol == "cm_copy_layer") {
-    if (active_cellview_index () >= 0) {
-      cm_copy_layer ();
-    }
-  } else if (symbol == "cm_new_layer") {
-    if (active_cellview_index () >= 0) {
-      cm_new_layer ();
-    }
-  } else if (symbol == "cm_layout_props") {
-    LayoutPropertiesForm lp_form (this, this, "layout_props_form");
-    lp_form.exec ();
-  } else if (symbol == "cm_layout_stats") {
-    LayoutStatisticsForm lp_form (this, this, "layout_props_form");
-    lp_form.exec ();
-  } else if (symbol == "cm_reload") {
-    cm_reload ();
-  } else if (symbol == "cm_inc_max_hier") {
-    int new_to = get_max_hier_levels () + 1;
-    set_hier_levels (std::make_pair (get_min_hier_levels (), new_to));
-  } else if (symbol == "cm_dec_max_hier") {
-    int new_to = get_max_hier_levels () > 0 ? get_max_hier_levels () - 1 : 0;
-    set_hier_levels (std::make_pair (std::min (get_min_hier_levels (), new_to), new_to));
-  } else if (symbol == "cm_max_hier") {
-    max_hier ();
-  } else if (symbol == "cm_max_hier_0") {
-    set_hier_levels (std::make_pair (std::min (get_min_hier_levels (), 0), 0));
-  } else if (symbol == "cm_max_hier_1") {
-    set_hier_levels (std::make_pair (std::min (get_min_hier_levels (), 0), 1));
-  } else if (symbol == "cm_prev_display_state") {
-    if (has_prev_display_state ()) {
-      prev_display_state ();
-    }
-  } else if (symbol == "cm_next_display_state") {
-    if (has_next_display_state ()) {
-      next_display_state ();
-    }
-  } else if (symbol == "cm_redraw") {
-    redraw ();
-  } else if (symbol == "cm_cell_delete") {
-    cm_cell_delete ();
-  } else if (symbol == "cm_cell_replace") {
-    cm_cell_replace ();
-  } else if (symbol == "cm_cell_rename") {
-    cm_cell_rename ();
-  } else if (symbol == "cm_cell_flatten") {
-    cm_cell_flatten ();
-  } else if (symbol == "cm_cell_select") {
-    cm_cell_select ();
-  } else if (symbol == "cm_cell_hide") {
-    cm_cell_hide ();
-  } else if (symbol == "cm_cell_show") {
-    cm_cell_show ();
-  } else if (symbol == "cm_cell_show_all") {
-    cm_cell_show_all ();
-  } else if (symbol == "cm_cell_user_properties") {
-    if (active_cellview_index () >= 0) {
-      cm_cell_user_properties ();
-    }
-  } else if (symbol == "cm_lv_select_all") {
-    cm_select_all ();
-  } else if (symbol == "cm_lv_new_tab") {
-    cm_new_tab ();
-  } else if (symbol == "cm_lv_rename_tab") {
-    cm_rename_tab ();
-  } else if (symbol == "cm_lv_make_invalid") {
-    cm_make_invalid ();
-  } else if (symbol == "cm_lv_remove_tab") {
-    cm_remove_tab ();
-  } else if (symbol == "cm_lv_make_valid") {
-    cm_make_valid ();
-  } else if (symbol == "cm_lv_hide_all") {
-    cm_hide_all ();
-  } else if (symbol == "cm_lv_hide") {
-    cm_hide ();
-  } else if (symbol == "cm_lv_show_only") {
-    cm_show_only ();
-  } else if (symbol == "cm_lv_show_all") {
-    cm_show_all ();
-  } else if (symbol == "cm_lv_show") {
-    cm_show ();
-  } else if (symbol == "cm_lv_rename") {
-    cm_rename ();
-  } else if (symbol == "cm_lv_delete") {
-    cm_delete ();
-  } else if (symbol == "cm_lv_insert") {
-    cm_insert ();
-  } else if (symbol == "cm_lv_group") {
-    cm_group ();
-  } else if (symbol == "cm_lv_ungroup") {
-    cm_ungroup ();
-  } else if (symbol == "cm_lv_source") {
-    cm_source ();
-  } else if (symbol == "cm_lv_sort_by_name") {
-    cm_sort_by_name ();
-  } else if (symbol == "cm_lv_sort_by_ild") {
-    cm_sort_by_ild ();
-  } else if (symbol == "cm_lv_sort_by_idl") {
-    cm_sort_by_idl ();
-  } else if (symbol == "cm_lv_sort_by_ldi") {
-    cm_sort_by_ldi ();
-  } else if (symbol == "cm_lv_sort_by_dli") {
-    cm_sort_by_dli ();
-  } else if (symbol == "cm_lv_regroup_by_index") {
-    cm_regroup_by_index ();
-  } else if (symbol == "cm_lv_regroup_by_datatype") {
-    cm_regroup_by_datatype ();
-  } else if (symbol == "cm_lv_regroup_by_layer") {
-    cm_regroup_by_layer ();
-  } else if (symbol == "cm_lv_regroup_flatten") {
-    cm_regroup_flatten ();
-  } else if (symbol == "cm_lv_expand_all") {
-    cm_expand_all ();
-  } else if (symbol == "cm_lv_add_missing") {
-    cm_add_missing ();
-  } else if (symbol == "cm_lv_remove_unused") {
-    cm_remove_unused ();
-  } else {
-
-    //  distribute the menu on the plugins - one should take it.
-    for (std::vector<lay::Plugin *>::iterator p = mp_plugins.begin (); p != mp_plugins.end (); ++p) {
-      (*p)->menu_activated (symbol);
-    }
-
+  //  distribute the menu item call on the plugins - one should take it.
+  for (std::vector<lay::Plugin *>::const_iterator p = plugins ().begin (); p != plugins ().end (); ++p) {
+    (*p)->menu_activated (symbol);
   }
 }
 
@@ -7132,229 +5866,6 @@ LayoutView::new_cell (int cv_index, const std::string &cell_name)
   return new_ci;
 }
 
-void
-LayoutView::do_transform (const db::DCplxTrans &tr)
-{
-  //  end move operations, cancel edit operations
-  cancel_edits ();
-  lay::Editables::transform (tr);
-}
-
-void
-LayoutView::transform_layout (const db::DCplxTrans &tr_mic)
-{
-  //  end move operations, cancel edit operations
-  cancel_edits ();
-  clear_selection ();
-
-  int cv_index = active_cellview_index ();
-  if (cv_index >= 0) {
-
-    db::Layout &layout = cellview (cv_index)->layout ();
-
-    db::ICplxTrans tr (db::DCplxTrans (1.0 / layout.dbu ()) * tr_mic * db::DCplxTrans (layout.dbu ()));
-
-    bool has_proxy = false;
-    for (db::Layout::const_iterator c = layout.begin (); ! has_proxy && c != layout.end (); ++c) {
-      has_proxy = c->is_proxy ();
-    }
-
-    if (has_proxy && 
-        QMessageBox::question (this, 
-                               QObject::tr ("Transforming PCells Or Library Cells"), 
-                               QObject::tr ("The layout contains PCells or library cells or both.\n"
-                                            "Any changes to such cells may be lost when their layout is refreshed later.\n"
-                                            "Consider using 'Convert all cells to static' before transforming the layout.\n"
-                                            "\n"
-                                            "Would you like to continue?\n"
-                                            "Choose 'Yes' to continue anyway. Choose 'No' to cancel."), 
-                               QMessageBox::Yes | QMessageBox::No) != QMessageBox::Yes) {
-      return;
-    }
-
-    transaction (tl::to_string (QObject::tr ("Transform layout")));
-    layout.transform (tr);
-    commit ();
-
-  }
-}
-
-void 
-LayoutView::cm_lay_flip_x ()
-{
-  transform_layout (db::DCplxTrans (db::FTrans::m90));
-}
-
-void 
-LayoutView::cm_lay_flip_y ()
-{
-  transform_layout (db::DCplxTrans (db::FTrans::m0));
-}
-
-void 
-LayoutView::cm_lay_rot_ccw ()
-{
-  db::DCplxTrans tr (db::DFTrans::r90);
-  transform_layout (db::DCplxTrans (db::FTrans::r90));
-}
-
-void 
-LayoutView::cm_lay_rot_cw ()
-{
-  transform_layout (db::DCplxTrans (db::FTrans::r270));
-}
-
-void 
-LayoutView::cm_lay_free_rot ()
-{
-  bool ok = false;
-  QString s = QInputDialog::getText (QApplication::activeWindow (), 
-                                     QObject::tr ("Free rotation"), 
-                                     QObject::tr ("Rotation angle in degree (counterclockwise)"), 
-                                     QLineEdit::Normal, QString::fromUtf8 ("0.0"), 
-                                     &ok);
-
-  if (ok) {
-
-    double angle = 0.0;
-    tl::from_string (tl::to_string (s), angle);
-
-    transform_layout (db::DCplxTrans (1.0, angle, false, db::DVector ()));
-
-  }
-}
-
-void 
-LayoutView::cm_lay_scale ()
-{
-  bool ok = false;
-  QString s = QInputDialog::getText (QApplication::activeWindow (), 
-                                     QObject::tr ("Scaling"), 
-                                     QObject::tr ("Scaling factor"), 
-                                     QLineEdit::Normal, QString::fromUtf8 ("1.0"), 
-                                     &ok);
-
-  if (ok) {
-
-    double scale = 0.0;
-    tl::from_string (tl::to_string (s), scale);
-
-    transform_layout (db::DCplxTrans (scale));
-
-  }
-}
-
-void 
-LayoutView::cm_lay_move ()
-{
-  lay::MoveOptionsDialog options (this);
-  if (options.exec_dialog (m_move_dist)) {
-    transform_layout (db::DCplxTrans (m_move_dist));
-  }
-}
-
-void 
-LayoutView::cm_sel_flip_x ()
-{
-  db::DCplxTrans tr (db::DFTrans::m90);
-  db::DBox sel_bbox (lay::Editables::selection_bbox ());
-  if (! sel_bbox.empty ()) {
-    tr = db::DCplxTrans (sel_bbox.center () - db::DPoint ()) * tr * db::DCplxTrans (db::DPoint () - sel_bbox.center ());
-  }
-  do_transform (tr);
-}
-
-void 
-LayoutView::cm_sel_flip_y ()
-{
-  db::DCplxTrans tr (db::DFTrans::m0);
-  db::DBox sel_bbox (lay::Editables::selection_bbox ());
-  if (! sel_bbox.empty ()) {
-    tr = db::DCplxTrans (sel_bbox.center () - db::DPoint ()) * tr * db::DCplxTrans (db::DPoint () - sel_bbox.center ());
-  }
-  do_transform (tr);
-}
-
-void 
-LayoutView::cm_sel_rot_ccw ()
-{
-  db::DCplxTrans tr (db::DFTrans::r90);
-  db::DBox sel_bbox (lay::Editables::selection_bbox ());
-  if (! sel_bbox.empty ()) {
-    tr = db::DCplxTrans (sel_bbox.center () - db::DPoint ()) * tr * db::DCplxTrans (db::DPoint () - sel_bbox.center ());
-  }
-  do_transform (tr);
-}
-
-void 
-LayoutView::cm_sel_rot_cw ()
-{
-  db::DCplxTrans tr (db::DFTrans::r270);
-  db::DBox sel_bbox (lay::Editables::selection_bbox ());
-  if (! sel_bbox.empty ()) {
-    tr = db::DCplxTrans (sel_bbox.center () - db::DPoint ()) * tr * db::DCplxTrans (db::DPoint () - sel_bbox.center ());
-  }
-  do_transform (tr);
-}
-
-void 
-LayoutView::cm_sel_free_rot ()
-{
-  bool ok = false;
-  QString s = QInputDialog::getText (QApplication::activeWindow (), 
-                                     QObject::tr ("Free rotation"), 
-                                     QObject::tr ("Rotation angle in degree (counterclockwise)"), 
-                                     QLineEdit::Normal, QString::fromUtf8 ("0.0"), 
-                                     &ok);
-
-  if (ok) {
-
-    double angle = 0.0;
-    tl::from_string (tl::to_string (s), angle);
-
-    db::DCplxTrans tr = db::DCplxTrans (1.0, angle, false, db::DVector ());
-    db::DBox sel_bbox (lay::Editables::selection_bbox ());
-    if (! sel_bbox.empty ()) {
-      tr = db::DCplxTrans (sel_bbox.center () - db::DPoint ()) * tr * db::DCplxTrans (db::DPoint () - sel_bbox.center ());
-    }
-    do_transform (tr);
-
-  }
-}
-
-void 
-LayoutView::cm_sel_scale ()
-{
-  bool ok = false;
-  QString s = QInputDialog::getText (QApplication::activeWindow (), 
-                                     QObject::tr ("Scaling"), 
-                                     QObject::tr ("Scaling factor"), 
-                                     QLineEdit::Normal, QString::fromUtf8 ("1.0"), 
-                                     &ok);
-
-  if (ok) {
-
-    double scale = 0.0;
-    tl::from_string (tl::to_string (s), scale);
-
-    db::DCplxTrans tr = db::DCplxTrans (scale);
-    db::DBox sel_bbox (lay::Editables::selection_bbox ());
-    if (! sel_bbox.empty ()) {
-      tr = db::DCplxTrans (sel_bbox.center () - db::DPoint ()) * tr * db::DCplxTrans (db::DPoint () - sel_bbox.center ());
-    }
-    do_transform (tr);
-
-  }
-}
-
-void
-LayoutView::cm_sel_move_interactive ()
-{
-  if (mp_move_service->begin_move ()) {
-    switch_mode (-1);  //  move mode
-  }
-}
-
 void
 LayoutView::switch_mode (int m)
 {
@@ -7364,400 +5875,6 @@ LayoutView::switch_mode (int m)
   }
 }
 
-void 
-LayoutView::cm_sel_move_to ()
-{
-  db::DBox sel_bbox (lay::Editables::selection_bbox ());
-  if (sel_bbox.empty ()) {
-    throw tl::Exception (tl::to_string (QObject::tr ("Nothing selected to move")));
-  }
-
-  double x = sel_bbox.left () + (sel_bbox.width () * (1 + m_move_to_origin_mode_x) * 0.5);
-  double y = sel_bbox.bottom () + (sel_bbox.height () * (1 + m_move_to_origin_mode_y) * 0.5);
-  db::DPoint move_target (x, y);
-
-  lay::MoveToOptionsDialog options (this);
-  if (options.exec_dialog (m_move_to_origin_mode_x, m_move_to_origin_mode_y, move_target)) {
-
-    x = sel_bbox.left () + (sel_bbox.width () * (1 + m_move_to_origin_mode_x) * 0.5);
-    y = sel_bbox.bottom () + (sel_bbox.height () * (1 + m_move_to_origin_mode_y) * 0.5);
-
-    do_transform (db::DCplxTrans (move_target - db::DPoint (x, y)));
-
-  }
-}
-
-void 
-LayoutView::cm_sel_move ()
-{
-  lay::MoveOptionsDialog options (this);
-  if (options.exec_dialog (m_move_dist)) {
-    do_transform (db::DCplxTrans (m_move_dist));
-  }
-}
-
-void
-LayoutView::cm_copy_layer () 
-{
-  struct { int *cv; int *layer; } specs [] = {
-    { &m_copy_cva, &m_copy_layera },
-    { &m_copy_cvr, &m_copy_layerr }
-  };
-
-  for (unsigned int i = 0; i < sizeof (specs) / sizeof (specs[0]); ++i) {
-
-    int &cv = *(specs[i].cv);
-    int &layer = *(specs[i].layer);
-
-    if (cv >= int (m_cellviews.size ())) {
-      cv = -1;
-    }
-
-    int index = active_cellview_index ();
-    if (cv < 0) {
-      cv = index;
-    }
-
-    if (cv < 0 || ! (*cellview_iter (cv))->layout ().is_valid_layer ((unsigned int) layer)) {
-      layer = -1;
-    }
-
-  }
-
-  lay::DuplicateLayerDialog dialog (this);
-  if (dialog.exec_dialog (this, m_copy_cva, m_copy_layera, m_copy_cvr, m_copy_layerr, m_duplicate_hier_mode, m_clear_before)) {
-
-    bool supports_undo = true;
-
-    if (manager () && manager ()->is_enabled ()) {
-
-      lay::TipDialog td (QApplication::activeWindow (), 
-                         tl::to_string (QObject::tr ("Undo buffering for the following operation can be memory and time consuming.\nChoose \"Yes\" to use undo buffering or \"No\" for no undo buffering. Warning: in the latter case, the undo history will be lost.\n\nChoose undo buffering?")), 
-                         "copy-layer-undo-buffering",
-                         lay::TipDialog::yesnocancel_buttons);
-
-      lay::TipDialog::button_type button = lay::TipDialog::null_button;
-      td.exec_dialog (button);
-      if (button == lay::TipDialog::cancel_button) {
-        return;
-      }
-
-      supports_undo = (button == lay::TipDialog::yes_button);
-
-    } else {
-      supports_undo = false;
-    }
-
-    cancel ();
-
-    if (manager ()) {
-      if (! supports_undo) {
-        manager ()->clear ();
-      } else {
-        manager ()->transaction (tl::to_string (QObject::tr ("Duplicate layer"))); 
-      }
-    }
-
-    try {
-
-      bool same_layout = (&cellview (m_copy_cvr)->layout () == &cellview (m_copy_cva)->layout ());
-      if (same_layout && m_copy_layera == m_copy_layerr) {
-        throw tl::Exception (tl::to_string (QObject::tr ("Source and target layer must not be identical for duplicate operation")));
-      }
-
-      if (m_duplicate_hier_mode == 0) {
-
-        //  clear the result layer for all called cells in flat mode
-        if (m_clear_before) {
-          std::set<db::cell_index_type> called_cells;
-          called_cells.insert (cellview (m_copy_cvr).cell_index ());
-          cellview (m_copy_cvr).cell ()->collect_called_cells (called_cells);
-          for (std::set<db::cell_index_type>::const_iterator c = called_cells.begin (); c != called_cells.end (); ++c) {
-            cellview (m_copy_cvr)->layout ().cell (*c).shapes (m_copy_layerr).clear ();
-          }
-        }
-
-        db::Cell &target_cell = *cellview (m_copy_cvr).cell ();
-
-        if (! same_layout) {
-
-          //  flat mode (different layouts)
-          db::PropertyMapper pm (cellview (m_copy_cvr)->layout (), cellview (m_copy_cva)->layout ());
-          for (db::RecursiveShapeIterator si (cellview (m_copy_cva)->layout (), *cellview (m_copy_cva).cell (), m_copy_layera); ! si.at_end (); ++si) {
-            target_cell.shapes (m_copy_layerr).insert (*si, si.trans (), pm);
-          }
-
-        } else {
-
-          //  flat mode (same layouts)
-          tl::ident_map<db::Layout::properties_id_type> pm1;
-          db::Shapes &res = target_cell.shapes (m_copy_layerr);
-          
-          db::Layout &layout = cellview (m_copy_cvr)->layout ();
-          try {
-
-            //  using update/start_layout and end_changes improves the performance since changing the 
-            //  shapes collection will invalidate the layout and cause updates inside the RecursiveShapeIerator
-            layout.update ();
-            layout.start_changes ();
-            for (db::RecursiveShapeIterator si (cellview (m_copy_cva)->layout (), *cellview (m_copy_cva).cell (), m_copy_layera); ! si.at_end (); ++si) {
-              res.insert (*si, si.trans (), pm1);
-            }
-            layout.end_changes ();
-
-          } catch (...) {
-            layout.end_changes ();
-            throw;
-          }
-
-        }
-        
-      } else if (m_duplicate_hier_mode == 1) {
-
-        db::Cell &cell = *cellview (m_copy_cva).cell ();
-        db::Cell &target_cell = *cellview (m_copy_cvr).cell ();
-
-        if (m_clear_before) {
-          target_cell.clear (m_copy_layerr);
-        } 
-
-        if (m_copy_cvr == m_copy_cva) {
-
-          //  current cell only mode: identical cell
-          cell.copy (m_copy_layera, m_copy_layerr);
-
-        } else if (! same_layout) {
-
-          //  current cell only mode (different layouts)
-          db::PropertyMapper pm (cellview (m_copy_cvr)->layout (), cellview (m_copy_cva)->layout ());
-          for (db::Shapes::shape_iterator si = cellview (m_copy_cva).cell ()->shapes (m_copy_layera).begin (db::ShapeIterator::All); ! si.at_end (); ++si) {
-            target_cell.shapes (m_copy_layerr).insert (*si, pm);
-          }
-
-        } else {
-
-          //  current cell only mode (same layouts, but different cells)
-          for (db::Shapes::shape_iterator si = cellview (m_copy_cva).cell ()->shapes (m_copy_layera).begin (db::ShapeIterator::All); ! si.at_end (); ++si) {
-            target_cell.shapes (m_copy_layerr).insert (*si);
-          }
-
-        }
-        
-      } else if (m_duplicate_hier_mode == 2) {
-
-        //  subcells cell by cell - source and target layout must be identical
-        std::set<db::cell_index_type> called_cells;
-        cellview (m_copy_cva).cell ()->collect_called_cells (called_cells);
-        called_cells.insert (cellview (m_copy_cva).cell_index ());
-
-        db::Layout &layout = cellview (m_copy_cva)->layout ();
-        for (std::set<db::cell_index_type>::const_iterator c = called_cells.begin (); c != called_cells.end (); ++c) {
-          db::Cell &cell = layout.cell (*c);
-          if (m_clear_before) {
-            cell.clear (m_copy_layerr);
-          } 
-          cell.copy (m_copy_layera, m_copy_layerr);
-        }
-
-      }
-
-      if (manager () && supports_undo) {
-        manager ()->commit ();
-      }
-
-    } catch (...) {
-      if (manager () && supports_undo) {
-        manager ()->commit ();
-      }
-      throw;
-    }
-
-  }
-}
-
-void
-LayoutView::cm_new_layer () 
-{
-  int index = active_cellview_index ();
-
-  if (index >= 0 && int (m_cellviews.size ()) > index) {
-
-    const lay::CellView &cv = cellview (index);
-
-    lay::NewLayerPropertiesDialog prop_dia (this);
-    if (prop_dia.exec_dialog (cv, m_new_layer_props)) {
-
-      for (unsigned int l = 0; l < cv->layout ().layers (); ++l) {
-        if (cv->layout ().is_valid_layer (l) && cv->layout ().get_properties (l).log_equal (m_new_layer_props)) {
-          throw tl::Exception (tl::to_string (QObject::tr ("A layer with that signature already exists: ")) + m_new_layer_props.to_string ());
-        }
-      }
-
-      transaction (tl::to_string (QObject::tr ("New layer")));
-
-      unsigned int l = cv->layout ().insert_layer (m_new_layer_props);
-      std::vector <unsigned int> nl;
-      nl.push_back (l);
-      add_new_layers (nl, index);
-      update_content ();
-
-      commit ();
-
-    }
-
-  }
-}
-
-void
-LayoutView::cm_edit_layer () 
-{
-  lay::LayerPropertiesConstIterator sel = current_layer ();
-  if (sel.is_null ()) {
-    throw tl::Exception (tl::to_string (QObject::tr ("No layer selected for editing it's properties")));
-  }
-
-  int index = sel->cellview_index ();
-  if (sel->has_children () || index < 0 || int (m_cellviews.size ()) <= index || sel->layer_index () < 0) {
-    throw tl::Exception (tl::to_string (QObject::tr ("No valid layer selected for editing it's properties")));
-  }
-
-  const lay::CellView &cv = cellview (index);
-
-  db::LayerProperties layer_props = cv->layout ().get_properties ((unsigned int) sel->layer_index ());
-
-  lay::NewLayerPropertiesDialog prop_dia (this);
-  if (prop_dia.exec_dialog (cv, layer_props)) {
-
-    for (unsigned int l = 0; l < cv->layout ().layers (); ++l) {
-      if (cv->layout ().is_valid_layer (l) && int (l) != sel->layer_index () && cv->layout ().get_properties (l).log_equal (layer_props)) {
-        throw tl::Exception (tl::to_string (QObject::tr ("A layer with that signature already exists: ")) + layer_props.to_string ());
-      }
-    }
-
-    transaction (tl::to_string (QObject::tr ("Edit layer")));
-
-    cv->layout ().set_properties (sel->layer_index (), layer_props);
-
-    lay::LayerProperties lp (*sel);
-    lay::ParsedLayerSource s = lp.source (false);
-    s.layer (layer_props.layer);
-    s.datatype (layer_props.datatype);
-    if (! layer_props.name.empty ()) {
-      s.name (layer_props.name);
-    } else {
-      s.clear_name ();
-    }
-    lp.set_source (s);
-    set_properties (sel, lp);
-
-    update_content ();
-
-    commit ();
-
-  }
-}
-
-void
-LayoutView::cm_delete_layer () 
-{
-  std::vector<lay::LayerPropertiesConstIterator> sel = selected_layers ();
-  std::sort (sel.begin (), sel.end (), CompareLayerIteratorBottomUp ());
-
-  //  collect valid layers
-  std::vector<lay::LayerPropertiesConstIterator> valid_sel;
-  std::set<std::pair<db::Layout *, unsigned int> > valid_layers;
-  for (std::vector<lay::LayerPropertiesConstIterator>::const_iterator si = sel.begin (); si != sel.end (); ++si) {
-    int cv_index = (*si)->cellview_index ();
-    const lay::CellView &cv = cellview (cv_index);
-    if (!(*si)->has_children () && cv_index >= 0 && int (m_cellviews.size ()) > cv_index && (*si)->layer_index () >= 0 && cv.is_valid ()) {
-      valid_sel.push_back (*si);
-      valid_layers.insert (std::make_pair (&cv->layout (), (*si)->layer_index ()));
-    }
-  }
-
-  if (valid_sel.empty ()) {
-    throw tl::Exception (tl::to_string (QObject::tr ("No or no valid layer selected for deleting them")));
-  }
-
-  cancel_edits ();
-  clear_selection ();
-
-  transaction (tl::to_string (QObject::tr ("Delete layers")));
-
-  //  Hint: delete_layer must come before the layers are actually deleted in because
-  //  for undo this must be the last thing to do (otherwise the layout is not propertly set up)
-
-  for (std::vector<lay::LayerPropertiesConstIterator>::const_iterator si = valid_sel.begin (); si != valid_sel.end (); ++si) {
-    lay::LayerPropertiesConstIterator lp = *si;
-    delete_layer (lp);
-  }
-
-  for (std::set<std::pair<db::Layout *, unsigned int> >::const_iterator li = valid_layers.begin (); li != valid_layers.end(); ++li) {
-
-    unsigned int layer_index = li->second;
-    db::Layout *layout = li->first;
-
-    for (db::Layout::iterator c = layout->begin (); c != layout->end (); ++c) {
-      c->shapes (layer_index).clear ();
-    }
-
-    layout->delete_layer (layer_index);
-
-  }
-
-  update_content ();
-
-  commit ();
-}
-
-void
-LayoutView::cm_clear_layer () 
-{
-  std::vector<lay::LayerPropertiesConstIterator> sel = selected_layers ();
-  if (sel.empty ()) {
-    throw tl::Exception (tl::to_string (QObject::tr ("No layer selected for clearing")));
-  }
-
-  lay::ClearLayerModeDialog mode_dialog (this);
-  if (mode_dialog.exec_dialog (m_layer_hier_mode)) {
-
-    cancel_edits ();
-    clear_selection ();
-
-    transaction (tl::to_string (QObject::tr ("Clear layer")));
-
-    for (std::vector<lay::LayerPropertiesConstIterator>::const_iterator si = sel.begin (); si != sel.end (); ++si) {
-
-      if (! (*si)->has_children () && (*si)->layer_index () >= 0 && cellview ((*si)->cellview_index ()).is_valid ()) {
-
-        int layer_index = (*si)->layer_index ();
-        const lay::CellView &cv = cellview ((*si)->cellview_index ());
-
-        if (m_layer_hier_mode == 0) {
-          cv.cell ()->clear ((unsigned int) layer_index);
-        } else if (m_layer_hier_mode == 1) {
-
-          cv.cell ()->clear ((unsigned int) layer_index);
-
-          std::set <db::cell_index_type> called_cells;
-          cv.cell ()->collect_called_cells (called_cells);
-          for (std::set <db::cell_index_type>::const_iterator cc = called_cells.begin (); cc != called_cells.end (); ++cc) {
-            cv->layout ().cell (*cc).clear ((unsigned int) layer_index);
-          }
-
-        } else {
-          cv->layout ().clear_layer ((unsigned int) layer_index);
-        }
-
-      }
-
-    }
-
-    commit ();
-
-  }
-}
-
 template <class T, class Iter>
 static void make_unique_name (T *object, Iter from, Iter to)
 {
@@ -7954,203 +6071,4 @@ LayoutView::sizeHint () const
   }
 }
 
-// ------------------------------------------------------------
-//  Declaration of the "plugin" for the menu entries
-
-class LayoutViewPluginDeclaration
-  : public lay::PluginDeclaration
-{
-public:
-  virtual void get_menu_entries (std::vector<lay::MenuEntry> &menu_entries) const
-  {
-    std::string at;
-
-    //  secret menu entries
-    at = "@secrets.end";
-    menu_entries.push_back (lay::menu_item ("cm_paste_interactive", "paste_interactive:edit", at, tl::to_string (QObject::tr ("Paste Interactive"))));
-    menu_entries.push_back (lay::menu_item ("cm_duplicate_interactive", "duplicate_interactive:edit", at, tl::to_string (QObject::tr ("Duplicate Interactive"))));
-    menu_entries.push_back (lay::menu_item ("cm_sel_move_interactive", "sel_move_interactive:edit", at, tl::to_string (QObject::tr ("Move Interactive"))));
-
-    at = "edit_menu.end";
-    menu_entries.push_back (lay::menu_item ("cm_undo", "undo:edit", at, tl::to_string (QObject::tr ("Undo(Ctrl+Z)"))));
-    menu_entries.push_back (lay::menu_item ("cm_redo", "redo:edit", at, tl::to_string (QObject::tr ("Redo(Ctrl+Y)"))));
-
-    menu_entries.push_back (lay::separator ("basic_group", at));
-    menu_entries.push_back (lay::submenu ("layout_menu:edit:edit_mode", at, tl::to_string (QObject::tr ("Layout"))));
-    {
-      std::string at = "edit_menu.layout_menu.end";
-      menu_entries.push_back (lay::menu_item ("cm_lay_flip_x", "lay_flip_x:edit_mode", at, tl::to_string (QObject::tr ("Flip Horizontally"))));
-      menu_entries.push_back (lay::menu_item ("cm_lay_flip_y", "lay_flip_y:edit_mode", at, tl::to_string (QObject::tr ("Flip Vertically"))));
-      menu_entries.push_back (lay::menu_item ("cm_lay_rot_cw", "lay_rot_cw:edit_mode", at, tl::to_string (QObject::tr ("Rotate Clockwise"))));
-      menu_entries.push_back (lay::menu_item ("cm_lay_rot_ccw", "lay_rot_ccw:edit_mode", at, tl::to_string (QObject::tr ("Rotate Counterclockwise"))));
-      menu_entries.push_back (lay::menu_item ("cm_lay_free_rot", "lay_free_rot:edit_mode", at, tl::to_string (QObject::tr ("Rotation By Angle"))));
-      menu_entries.push_back (lay::menu_item ("cm_lay_scale", "lay_scale:edit_mode", at, tl::to_string (QObject::tr ("Scale"))));
-      menu_entries.push_back (lay::menu_item ("cm_lay_move", "lay_move:edit_mode", at, tl::to_string (QObject::tr ("Move By"))));
-      menu_entries.push_back (lay::separator ("cellop_group", at));
-      menu_entries.push_back (lay::menu_item ("cm_lay_convert_to_static", "lay_convert_to_static:edit_mode", at, tl::to_string (QObject::tr ("Convert All Cells To Static"))));
-    }
-
-    menu_entries.push_back (lay::submenu ("cell_menu:edit:edit_mode", at, tl::to_string (QObject::tr ("Cell"))));
-    {
-      std::string at = "edit_menu.cell_menu.end";
-      menu_entries.push_back (lay::menu_item ("cm_new_cell", "new_cell:edit:edit_mode", at, tl::to_string (QObject::tr ("New Cell"))));
-      menu_entries.push_back (lay::menu_item ("cm_cell_delete", "delete_cell:edit:edit_mode", at, tl::to_string (QObject::tr ("Delete Cell"))));
-      menu_entries.push_back (lay::menu_item ("cm_cell_rename", "rename_cell:edit:edit_mode", at, tl::to_string (QObject::tr ("Rename Cell"))));
-      menu_entries.push_back (lay::menu_item ("cm_cell_replace", "replace_cell:edit:edit_mode", at, tl::to_string (QObject::tr ("Replace Cell"))));
-      menu_entries.push_back (lay::menu_item ("cm_cell_flatten", "flatten_cell:edit:edit_mode", at, tl::to_string (QObject::tr ("Flatten Cell"))));
-      menu_entries.push_back (lay::separator ("ops_group", at));
-      menu_entries.push_back (lay::menu_item ("cm_adjust_origin", "adjust_cell_origin:edit:edit_mode", at, tl::to_string (QObject::tr ("Adjust Origin"))));
-      menu_entries.push_back (lay::menu_item ("cm_cell_convert_to_static", "convert_cell_to_static:edit_mode", at, tl::to_string (QObject::tr ("Convert Cell To Static"))));
-      menu_entries.push_back (lay::separator ("props_group", at));
-      menu_entries.push_back (lay::menu_item ("cm_cell_user_properties", "user_properties", at, tl::to_string (QObject::tr ("User Properties"))));
-    }
-
-    menu_entries.push_back (lay::submenu ("layer_menu:edit:edit_mode", at, tl::to_string (QObject::tr ("Layer"))));
-    {
-      std::string at = "edit_menu.layer_menu.end";
-      menu_entries.push_back (lay::menu_item ("cm_new_layer", "new_layer:edit:edit_mode", at, tl::to_string (QObject::tr ("New Layer"))));
-      menu_entries.push_back (lay::menu_item ("cm_clear_layer", "clear_layer:edit:edit_mode", at, tl::to_string (QObject::tr ("Clear Layer"))));
-      menu_entries.push_back (lay::menu_item ("cm_delete_layer", "delete_layer:edit:edit_mode", at, tl::to_string (QObject::tr ("Delete Layer"))));
-      menu_entries.push_back (lay::menu_item ("cm_copy_layer", "copy_layer:edit:edit_mode", at, tl::to_string (QObject::tr ("Copy Layer"))));
-      menu_entries.push_back (lay::menu_item ("cm_edit_layer", "edit_layer:edit:edit_mode", at, tl::to_string (QObject::tr ("Edit Layer Specification"))));
-    }
-
-    menu_entries.push_back (lay::submenu ("selection_menu:edit", at, tl::to_string (QObject::tr ("Selection"))));
-    {
-      std::string at = "edit_menu.selection_menu.end";
-      menu_entries.push_back (lay::menu_item ("cm_sel_flip_x", "sel_flip_x", at, tl::to_string (QObject::tr ("Flip Horizontally"))));
-      menu_entries.push_back (lay::menu_item ("cm_sel_flip_y", "sel_flip_y", at, tl::to_string (QObject::tr ("Flip Vertically"))));
-      menu_entries.push_back (lay::menu_item ("cm_sel_rot_cw", "sel_rot_cw", at, tl::to_string (QObject::tr ("Rotate Clockwise"))));
-      menu_entries.push_back (lay::menu_item ("cm_sel_rot_ccw", "sel_rot_ccw", at, tl::to_string (QObject::tr ("Rotate Counterclockwise"))));
-      menu_entries.push_back (lay::menu_item ("cm_sel_free_rot", "sel_free_rot", at, tl::to_string (QObject::tr ("Rotation By Angle"))));
-      menu_entries.push_back (lay::menu_item ("cm_sel_scale", "sel_scale", at, tl::to_string (QObject::tr ("Scale"))));
-      menu_entries.push_back (lay::menu_item ("cm_sel_move", "sel_move", at, tl::to_string (QObject::tr ("Move By"))));
-      menu_entries.push_back (lay::menu_item ("cm_sel_move_to", "sel_move_to", at, tl::to_string (QObject::tr ("Move To"))));
-    }
-
-    menu_entries.push_back (lay::separator ("utils_group", at));
-    menu_entries.push_back (lay::submenu ("utils_menu:edit:edit_mode", at, tl::to_string (QObject::tr ("Utilities"))));
-
-    menu_entries.push_back (lay::separator ("misc_group", at));
-    menu_entries.push_back (lay::menu_item ("cm_delete", "delete:edit", at, tl::to_string (QObject::tr ("Delete(Del)"))));
-    menu_entries.push_back (lay::menu_item ("cm_show_properties", "show_properties:edit", at, tl::to_string (QObject::tr ("Properties(Q)"))));
-
-    menu_entries.push_back (lay::separator ("cpc_group", at));
-    menu_entries.push_back (lay::menu_item ("cm_copy", "copy:edit", at, tl::to_string (QObject::tr ("Copy(Ctrl+C)"))));
-    menu_entries.push_back (lay::menu_item ("cm_cut", "cut:edit", at, tl::to_string (QObject::tr ("Cut(Ctrl+X)"))));
-    menu_entries.push_back (lay::menu_item ("cm_paste", "paste:edit", at, tl::to_string (QObject::tr ("Paste(Ctrl+V)"))));
-    menu_entries.push_back (lay::menu_item ("cm_duplicate", "duplicate:edit", at, tl::to_string (QObject::tr ("Duplicate(Ctrl+B)"))));
-
-    menu_entries.push_back (lay::separator ("modes_group", at));
-    menu_entries.push_back (lay::submenu ("mode_menu", at, tl::to_string (QObject::tr ("Mode"))));
-
-    menu_entries.push_back (lay::submenu ("select_menu", at, tl::to_string (QObject::tr ("Select"))));
-    {
-      std::string at = "edit_menu.select_menu.end";
-      menu_entries.push_back (lay::menu_item ("cm_select_all", "select_all", at, tl::to_string (QObject::tr ("Select All"))));
-      menu_entries.push_back (lay::menu_item ("cm_unselect_all", "unselect_all", at, tl::to_string (QObject::tr ("Unselect All"))));
-      menu_entries.push_back (lay::separator ("edit_select_basic_group", at));
-      menu_entries.push_back (lay::menu_item ("lv:enable_all", "enable_all", at, tl::to_string (QObject::tr ("Enable All"))));
-      menu_entries.push_back (lay::menu_item ("lv:disable_all", "disable_all", at, tl::to_string (QObject::tr ("Disable All"))));
-      menu_entries.push_back (lay::separator ("edit_select_individual_group", at));
-    };
-
-    menu_entries.push_back (lay::separator ("cancel_group", at));
-    menu_entries.push_back (lay::menu_item ("cm_cancel", "cancel", at, tl::to_string (QObject::tr ("Cancel(Esc)"))));
-
-    at = "bookmark_menu.end";
-    menu_entries.push_back (lay::submenu ("goto_bookmark_menu", at, tl::to_string (QObject::tr ("Goto Bookmark"))));
-    menu_entries.push_back (lay::menu_item ("cm_bookmark_view", "bookmark_view", at, tl::to_string (QObject::tr ("Bookmark This View"))));
-
-    menu_entries.push_back (lay::separator ("bookmark_mgm_group", at));
-    menu_entries.push_back (lay::menu_item ("cm_manage_bookmarks", "manage_bookmarks", at, tl::to_string (QObject::tr ("Manage Bookmarks"))));
-    menu_entries.push_back (lay::menu_item ("cm_load_bookmarks", "load_bookmarks", at, tl::to_string (QObject::tr ("Load Bookmarks"))));
-    menu_entries.push_back (lay::menu_item ("cm_save_bookmarks", "save_bookmarks", at, tl::to_string (QObject::tr ("Save Bookmarks"))));
-
-    at = "zoom_menu.end";
-    menu_entries.push_back (lay::submenu ("global_trans", at, tl::to_string (QObject::tr ("Global Transformation"))));
-    {
-      std::string at = "zoom_menu.global_trans.end";
-      menu_entries.push_back (lay::config_menu_item ("r0", at, tl::to_string (QObject::tr ("\\(r0\\)<:/r0.png>")), cfg_global_trans, "?r0 *1 0,0"));
-      menu_entries.push_back (lay::config_menu_item ("r90", at, tl::to_string (QObject::tr ("\\(r90\\)<:/r90.png>")), cfg_global_trans, "?r90 *1 0,0"));
-      menu_entries.push_back (lay::config_menu_item ("r180", at, tl::to_string (QObject::tr ("\\(r180\\)<:/r180.png>")), cfg_global_trans, "?r180 *1 0,0"));
-      menu_entries.push_back (lay::config_menu_item ("r270", at, tl::to_string (QObject::tr ("\\(r270\\)<:/r270.png>")), cfg_global_trans, "?r270 *1 0,0"));
-      menu_entries.push_back (lay::config_menu_item ("m0", at, tl::to_string (QObject::tr ("\\(m0\\)<:/m0.png>")), cfg_global_trans, "?m0 *1 0,0"));
-      menu_entries.push_back (lay::config_menu_item ("m45", at, tl::to_string (QObject::tr ("\\(m45\\)<:/m45.png>")), cfg_global_trans, "?m45 *1 0,0"));
-      menu_entries.push_back (lay::config_menu_item ("m90", at, tl::to_string (QObject::tr ("\\(m90\\)<:/m90.png>")), cfg_global_trans, "?m90 *1 0,0"));
-      menu_entries.push_back (lay::config_menu_item ("m135", at, tl::to_string (QObject::tr ("\\(m135\\)<:/m135.png>")), cfg_global_trans, "?m135 *1 0,0"));
-    }
-
-    menu_entries.push_back (lay::separator ("hier_group", at));
-    menu_entries.push_back (lay::menu_item ("cm_max_hier", "max_hier", at, tl::to_string (QObject::tr ("Full Hierarchy(*)"))));
-    menu_entries.push_back (lay::menu_item ("cm_max_hier_0", "max_hier_0", at, tl::to_string (QObject::tr ("Box Only(0)"))));
-    menu_entries.push_back (lay::menu_item ("cm_max_hier_1", "max_hier_1", at, tl::to_string (QObject::tr ("Top Level Only(1)"))));
-    menu_entries.push_back (lay::menu_item ("cm_inc_max_hier", "inc_max_hier", at, tl::to_string (QObject::tr ("Increment Hierarchy(+)"))));
-    menu_entries.push_back (lay::menu_item ("cm_dec_max_hier", "dec_max_hier", at, tl::to_string (QObject::tr ("Decrement Hierarchy(-)"))));
-
-    menu_entries.push_back (lay::separator ("zoom_group", at));
-    menu_entries.push_back (lay::menu_item ("cm_zoom_fit", "zoom_fit", at, tl::to_string (QObject::tr ("Zoom Fit(F2)"))));
-    menu_entries.push_back (lay::menu_item ("cm_zoom_fit_sel", "zoom_fit_sel", at, tl::to_string (QObject::tr ("Zoom Fit Selection(Shift+F2)"))));
-    menu_entries.push_back (lay::menu_item ("cm_zoom_in", "zoom_in", at, tl::to_string (QObject::tr ("Zoom In(Return)"))));
-    menu_entries.push_back (lay::menu_item ("cm_zoom_out", "zoom_out", at, tl::to_string (QObject::tr ("Zoom Out(Shift+Return)"))));
-    /* disabled because that interferes with the use of the arrow keys for moving the selection
-    MenuLayoutEntry::separator ("pan_group");
-    menu_entries.push_back (lay::menu_item ("cm_pan_up", "pan_up", at, tl::to_string (QObject::tr ("Pan Up(Up)"))));
-    menu_entries.push_back (lay::menu_item ("cm_pan_down", "pan_down", at, tl::to_string (QObject::tr ("Pan Down(Down)"))));
-    menu_entries.push_back (lay::menu_item ("cm_pan_left", "pan_left", at, tl::to_string (QObject::tr ("Pan Left(Left)"))));
-    menu_entries.push_back (lay::menu_item ("cm_pan_right", "pan_right", at, tl::to_string (QObject::tr ("Pan Right(Right)"))));
-    */
-
-    menu_entries.push_back (lay::separator ("redraw_group", at));
-    menu_entries.push_back (lay::menu_item ("cm_redraw", "redraw", at, tl::to_string (QObject::tr ("Redraw"))));
-    menu_entries.push_back (lay::separator ("state_group", at));
-    menu_entries.push_back (lay::menu_item_copy ("cm_prev_display_state", "prev_display_state", at, "@toolbar.prev_display_state"));
-    menu_entries.push_back (lay::menu_item_copy ("cm_next_display_state", "next_display_state", at, "@toolbar.next_display_state"));
-
-    menu_entries.push_back (lay::separator ("select_group", at));
-    menu_entries.push_back (lay::menu_item ("cm_select_cell", "select_cell:edit", at, tl::to_string (QObject::tr ("Select Cell"))));
-    menu_entries.push_back (lay::menu_item ("cm_select_current_cell", "select_current_cell", at, tl::to_string (QObject::tr ("Show As New Top(Ctrl+S)"))));
-    menu_entries.push_back (lay::menu_item ("cm_goto_position", "goto_position", at, tl::to_string (QObject::tr ("Goto Position(Ctrl+G)"))));
-
-    //  Add a hook for inserting new items after the modes
-    menu_entries.push_back (lay::separator ("end_modes", "@toolbar.end"));
-
-  }
-
-  bool menu_activated (const std::string &symbol) const
-  {
-    if (symbol == "lv:enable_all") {
-
-      for (tl::Registrar<lay::PluginDeclaration>::iterator cls = tl::Registrar<lay::PluginDeclaration>::begin (); cls != tl::Registrar<lay::PluginDeclaration>::end (); ++cls) {
-        cls->set_editable_enabled (true);
-      }
-      return true;
-
-    } else if (symbol == "lv:disable_all") {
-
-      for (tl::Registrar<lay::PluginDeclaration>::iterator cls = tl::Registrar<lay::PluginDeclaration>::begin (); cls != tl::Registrar<lay::PluginDeclaration>::end (); ++cls) {
-        cls->set_editable_enabled (false);
-      }
-      return true;
-
-    } else {
-      return false;
-    }
-  }
-
-  void implements_primary_mouse_modes (std::vector<std::pair<std::string, std::pair<std::string, int> > > &modes)
-  {
-    std::vector <std::string> mode_titles;
-    lay::LayoutView::intrinsic_mouse_modes (&mode_titles);
-
-    int mode_id = 0;
-    for (std::vector <std::string>::const_iterator t = mode_titles.begin (); t != mode_titles.end (); ++t, --mode_id) {
-      //  modes: pair(title, pair(insert_pos, id))
-      modes.push_back (std::make_pair (*t, std::make_pair ("edit_menu.mode_menu.end;@toolbar.end_modes", mode_id)));
-    }
-  }
-};
-
-static tl::RegisteredClass<lay::PluginDeclaration> config_decl (new LayoutViewPluginDeclaration (), -10, "LayoutViewPlugin");
-
 } // namespace lay
diff --git a/src/laybasic/laybasic/layLayoutView.h b/src/laybasic/laybasic/layLayoutView.h
index fc05c566e..66469b163 100644
--- a/src/laybasic/laybasic/layLayoutView.h
+++ b/src/laybasic/laybasic/layLayoutView.h
@@ -50,7 +50,7 @@
 #include "layPlugin.h"
 #include "layDisplayState.h"
 #include "layBookmarkList.h"
-#include "layDialogs.h"
+#include "layEditorOptionsFrame.h"
 #include "gsi.h"
 #include "tlException.h"
 #include "tlEvents.h"
@@ -83,6 +83,7 @@ class MoveService;
 class Browser;
 class ColorButton;
 class ConfigureAction;
+class EditorOptionsPages;
 
 /**
  *  @brief Stores a layer reference to create layers which have been added by some action
@@ -176,14 +177,15 @@ public:
     LV_NoLayers = 1, 
     LV_NoHierarchyPanel = 2, 
     LV_NoLibrariesView = 4,
-    LV_NoBookmarksView = 8,
-    LV_Naked = 16,
-    LV_NoZoom = 32,
-    LV_NoGrid = 64,
-    LV_NoMove = 128,
-    LV_NoTracker = 256,
-    LV_NoSelection = 512,
-    LV_NoPlugins = 1024,
+    LV_NoEditorOptionsPanel = 8,
+    LV_NoBookmarksView = 16,
+    LV_Naked = 32,
+    LV_NoZoom = 64,
+    LV_NoGrid = 128,
+    LV_NoMove = 256,
+    LV_NoTracker = 512,
+    LV_NoSelection = 1024,
+    LV_NoPlugins = 2048,
     LV_NoServices = LV_NoMove + LV_NoTracker + LV_NoSelection + LV_NoPlugins
   };
 
@@ -237,6 +239,14 @@ public:
     return mp_control_frame;
   }
 
+  /**
+   *  @brief Gets the layer control panel
+   */
+  lay::LayerControlPanel *control_panel ()
+  {
+    return mp_control_panel;
+  }
+
   /**
    *  @brief Gets the container with the hierarchy control panel
    */
@@ -245,6 +255,14 @@ public:
     return mp_hierarchy_frame;
   }
 
+  /**
+   *  @brief Gets the hierarchy panel
+   */
+  lay::HierarchyControlPanel *hierarchy_panel ()
+  {
+    return mp_hierarchy_panel;
+  }
+
   /**
    *  @brief Gets the container with the libraries view
    */
@@ -261,6 +279,19 @@ public:
     return mp_bookmarks_frame;
   }
 
+  /**
+   *  @brief Gets the container with the editor options
+   */
+  QWidget *editor_options_frame ()
+  {
+    return mp_editor_options_frame;
+  }
+
+  /**
+   *  @brief Gets the editor options pages widget
+   */
+  lay::EditorOptionsPages *editor_options_pages ();
+
   /**
    *  @brief Pastes from clipboard
    *
@@ -720,6 +751,12 @@ public:
    */
   tl::event<int> current_layer_list_changed_event;
 
+  /**
+   *  @brief An event signalling that the current layer has changed
+   */
+  tl::event<const lay::LayerPropertiesConstIterator &> current_layer_changed_event;
+
+
   /**
    *  @brief An event signalling that the visibility of some cells has changed
    */
@@ -743,8 +780,18 @@ public:
    *
    *  This method will look up that layer in the layer view tree and select that layer.
    *  This method will also select this layer.
+   *
+   *  Returns false if the layer is not a valid one.
    */
-  void set_current_layer (unsigned int cv_index, const db::LayerProperties &properties);
+  bool set_current_layer (unsigned int cv_index, const db::LayerProperties &properties);
+
+  /**
+   *  @brief Sets the currently active layer by layer properties and cell view index
+   *
+   *  If the layer does not exist, the user will be asked whether to create the layer.
+   *  Returns false if the layer is not a valid one and the user defined to create the layer.
+   */
+  bool set_or_request_current_layer (unsigned int cv_index, const db::LayerProperties &properties);
 
   /**
    *  @brief Sets the currently active layer
@@ -1958,6 +2005,14 @@ public:
    */
   virtual void drop_url (const std::string &path_or_url);
 
+  /**
+   *  @brief Gets a list of all plugins
+   */
+  const std::vector<lay::Plugin *> &plugins ()
+  {
+    return mp_plugins;
+  }
+
   /**
    *  @brief Localize a plugin by name
    *
@@ -2506,6 +2561,14 @@ public:
    */
   void create_plugins (const lay::PluginDeclaration *except_this = 0);
 
+  /**
+   *  @brief Gets the full field box
+   *
+   *  This is the box to which the view will zoom on zoom_fit().
+   *  This box is supposed to cover everything inside the view.
+   */
+  db::DBox full_box () const;
+
 public slots:
   /**
    *  @brief Store the current state on the "previous states" stack
@@ -2561,12 +2624,9 @@ public slots:
   void select_cell_dispatch (const cell_path_type &path, int cellview_index);
 
   /**
-   *  @brief Gets the full field box
-   *
-   *  This is the box to which the view will zoom on zoom_fit().
-   *  This box is supposed to cover everything inside the view.
+   *  @brief Called when the current layer changed
    */
-  db::DBox full_box () const;
+  void current_layer_changed_slot (const lay::LayerPropertiesConstIterator &iter);
 
   //  zoom slots
   void zoom_fit ();
@@ -2582,81 +2642,6 @@ public slots:
   void pan_right_fast ();
   void pan_down_fast ();
 
-  //  menu callbacks
-  void cm_new_layer ();
-  void cm_clear_layer ();
-  void cm_delete_layer ();
-  void cm_copy_layer ();
-  void cm_align_cell_origin ();
-  void cm_edit_layer ();
-  void cm_lay_convert_to_static ();
-  void cm_lay_flip_x ();
-  void cm_lay_flip_y ();
-  void cm_lay_rot_cw ();
-  void cm_lay_rot_ccw ();
-  void cm_lay_free_rot ();
-  void cm_lay_scale ();
-  void cm_lay_move ();
-  void cm_sel_flip_x ();
-  void cm_sel_flip_y ();
-  void cm_sel_rot_cw ();
-  void cm_sel_rot_ccw ();
-  void cm_sel_free_rot ();
-  void cm_sel_scale ();
-  void cm_sel_move ();
-  void cm_sel_move_to ();
-  void cm_sel_move_interactive ();
-
-  //  forwarded to the layer control panel
-  void cm_new_tab ();
-  void cm_rename_tab ();
-  void cm_remove_tab ();
-  void cm_select_all ();
-  void cm_make_valid ();
-  void cm_make_invalid ();
-  void cm_hide ();
-  void cm_hide_all ();
-  void cm_show ();
-  void cm_show_all ();
-  void cm_show_only ();
-  void cm_rename ();
-  void cm_delete ();
-  void cm_insert ();
-  void cm_group ();
-  void cm_ungroup ();
-  void cm_source ();
-  void cm_sort_by_name ();
-  void cm_sort_by_ild ();
-  void cm_sort_by_idl ();
-  void cm_sort_by_ldi ();
-  void cm_sort_by_dli ();
-  void cm_regroup_by_index ();
-  void cm_regroup_by_datatype ();
-  void cm_regroup_by_layer ();
-  void cm_regroup_flatten ();
-  void cm_expand_all ();
-  void cm_add_missing ();
-  void cm_remove_unused ();
-  void cm_layer_copy ();
-  void cm_layer_cut ();
-  void cm_layer_paste ();
-
-  //  forwarded to the cell control panel
-  void cm_cell_user_properties ();
-  void cm_cell_flatten ();
-  void cm_cell_rename ();
-  void cm_cell_replace ();
-  void cm_cell_delete ();
-  void cm_cell_select ();
-  void cm_open_current_cell ();
-  void cm_cell_hide ();
-  void cm_cell_show ();
-  void cm_cell_show_all ();
-  void cm_cell_copy ();
-  void cm_cell_cut ();
-  void cm_cell_paste ();
-  void cm_cell_convert_to_static ();
-
   //  called by children and owner
   void redraw ();
   void redraw_layer (unsigned int index);
@@ -2728,6 +2713,11 @@ signals:
    */
   void mode_change (int m);
 
+  /**
+   *  @brief The current layer changed
+   */
+  void current_layer_changed (const lay::LayerPropertiesConstIterator &l);
+
 protected:
   /**
    *  @brief Establish the view operations
@@ -2761,6 +2751,7 @@ private:
   lay::LibrariesView *mp_libraries_view;
   lay::BookmarksView *mp_bookmarks_view;
   QWidget *mp_control_frame, *mp_hierarchy_frame, *mp_libraries_frame, *mp_bookmarks_frame;
+  lay::EditorOptionsFrame *mp_editor_options_frame;
   QSpinBox *mp_min_hier_spbx;
   QSpinBox *mp_max_hier_spbx;
   std::list <CellView> m_cellviews;
@@ -2869,29 +2860,18 @@ private:
 
   std::vector<lay::Plugin *> mp_plugins;
 
-  db::LayerProperties m_new_layer_props;
-  db::DVector m_move_dist;
-  int m_move_to_origin_mode_x, m_move_to_origin_mode_y;
-  lay::AlignCellOptions m_align_cell_options;
-  int m_del_cell_mode;
-  int m_layer_hier_mode;
-  int m_duplicate_hier_mode;
-  bool m_clear_before;
-  int m_copy_cva, m_copy_cvr;
-  int m_copy_layera, m_copy_layerr;
-
   bool m_visibility_changed;
   bool m_active_cellview_changed_event_enabled;
   tl::DeferredMethod<lay::LayoutView> dm_prop_changed;
 
+  tl::DeferredMethod<lay::LayoutView> dm_setup_editor_option_pages;
+
   void init (db::Manager *mgr, QWidget *parent);
   void init_menu ();
 
   void do_prop_changed ();
   void do_redraw (int layer);
   void do_redraw ();
-  void do_transform (const db::DCplxTrans &tr);
-  void transform_layout (const db::DCplxTrans &tr);
 
   void background_color (QColor c);
   void ctx_color (QColor c);
@@ -2907,22 +2887,20 @@ private:
   int max_hier_level () const;
   bool set_hier_levels_basic (std::pair<int, int> l);
 
+  void do_setup_editor_options_pages ();
+
   void update_event_handlers ();
   void viewport_changed ();
   void cellview_changed (unsigned int index);
 
   bool configure (const std::string &name, const std::string &value);
+  void config_finalize ();
 
   void do_load_layer_props (const std::string &fn, bool map_cv, int cv_index, bool add_default);
   void finish_cellviews_changed ();
   void init_layer_properties (LayerProperties &props, const LayerPropertiesList &lp_list) const;
   void merge_dither_pattern (lay::LayerPropertiesList &props);
 
-  void do_cm_duplicate (bool interactive);
-  void do_cm_paste (bool interactive);
-  void cm_new_cell ();
-  void cm_reload ();
-
   //  overrides Editables method to display a message
   void signal_selection_changed ();
 
diff --git a/src/laybasic/laybasic/layLayoutViewConfigPages.cc b/src/laybasic/laybasic/layLayoutViewConfigPages.cc
index 30c4aa6bb..d2e66440e 100644
--- a/src/laybasic/laybasic/layLayoutViewConfigPages.cc
+++ b/src/laybasic/laybasic/layLayoutViewConfigPages.cc
@@ -31,6 +31,7 @@
 #include "ui_LayoutViewConfigPage2a.h"
 #include "ui_LayoutViewConfigPage2b.h"
 #include "ui_LayoutViewConfigPage2c.h"
+#include "ui_LayoutViewConfigPage2d.h"
 #include "ui_LayoutViewConfigPage3a.h"
 #include "ui_LayoutViewConfigPage3b.h"
 #include "ui_LayoutViewConfigPage3c.h"
@@ -389,6 +390,42 @@ LayoutViewConfigPage2c::commit (lay::Dispatcher *root)
   root->config_set (cfg_search_range, (unsigned int) mp_ui->search_range_spinbx->value ());
 }
 
+// ------------------------------------------------------------
+//  LayoutConfigPage2d implementation
+
+LayoutViewConfigPage2d::LayoutViewConfigPage2d (QWidget *parent)
+  : lay::ConfigPage (parent)
+{
+  mp_ui = new Ui::LayoutViewConfigPage2d ();
+  mp_ui->setupUi (this);
+}
+
+LayoutViewConfigPage2d::~LayoutViewConfigPage2d ()
+{
+  delete mp_ui;
+  mp_ui = 0;
+}
+
+void
+LayoutViewConfigPage2d::setup (lay::Dispatcher *root)
+{
+  QColor color;
+  root->config_get (cfg_tracking_cursor_color, color, lay::ColorConverter ());
+  mp_ui->color_pb->set_color (color);
+
+  bool enabled = 0;
+  root->config_get (cfg_tracking_cursor_enabled, enabled);
+  mp_ui->tracking_cb->setChecked (enabled);
+}
+
+void
+LayoutViewConfigPage2d::commit (lay::Dispatcher *root)
+{
+  lay::ColorConverter cc;
+  root->config_set (cfg_tracking_cursor_color, mp_ui->color_pb->get_color (), cc);
+  root->config_set (cfg_tracking_cursor_enabled, mp_ui->tracking_cb->isChecked ());
+}
+
 // ------------------------------------------------------------
 //  LayoutConfigPage3a implementation
 
@@ -1516,6 +1553,8 @@ public:
     options.push_back (std::pair<std::string, std::string> (cfg_sel_halo, "true"));
     options.push_back (std::pair<std::string, std::string> (cfg_sel_transient_mode, "true"));
     options.push_back (std::pair<std::string, std::string> (cfg_sel_inside_pcells_mode, "false"));
+    options.push_back (std::pair<std::string, std::string> (cfg_tracking_cursor_enabled, "true"));
+    options.push_back (std::pair<std::string, std::string> (cfg_tracking_cursor_color, cc.to_string (QColor ())));
     options.push_back (std::pair<std::string, std::string> (cfg_background_color, cc.to_string (QColor ())));
     options.push_back (std::pair<std::string, std::string> (cfg_ctx_color, cc.to_string (QColor ())));
     options.push_back (std::pair<std::string, std::string> (cfg_ctx_dimming, "50"));
@@ -1571,6 +1610,7 @@ public:
     pages.push_back (std::make_pair (tl::to_string (QObject::tr ("Display|Optimization")),    new LayoutViewConfigPage3f (parent)));
 
     pages.push_back (std::make_pair (tl::to_string (QObject::tr ("Application|Selection")),   new LayoutViewConfigPage2c (parent)));
+    pages.push_back (std::make_pair (tl::to_string (QObject::tr ("Application|Tracking")),    new LayoutViewConfigPage2d (parent)));
     pages.push_back (std::make_pair (tl::to_string (QObject::tr ("Application|Layer Properties")),  new LayoutViewConfigPage5 (parent)));
     pages.push_back (std::make_pair (tl::to_string (QObject::tr ("Application|Units")),       new LayoutViewConfigPage3c (parent)));
 
diff --git a/src/laybasic/laybasic/layLayoutViewConfigPages.h b/src/laybasic/laybasic/layLayoutViewConfigPages.h
index 10ffb7a23..1170a6a19 100644
--- a/src/laybasic/laybasic/layLayoutViewConfigPages.h
+++ b/src/laybasic/laybasic/layLayoutViewConfigPages.h
@@ -38,6 +38,7 @@ namespace Ui {
   class LayoutViewConfigPage2a;
   class LayoutViewConfigPage2b;
   class LayoutViewConfigPage2c;
+  class LayoutViewConfigPage2d;
   class LayoutViewConfigPage3a;
   class LayoutViewConfigPage3b;
   class LayoutViewConfigPage3c;
@@ -138,7 +139,23 @@ private:
   Ui::LayoutViewConfigPage2c *mp_ui;
 };
 
-class LayoutViewConfigPage3a 
+class LayoutViewConfigPage2d
+  : public lay::ConfigPage
+{
+Q_OBJECT
+
+public:
+  LayoutViewConfigPage2d (QWidget *parent);
+  ~LayoutViewConfigPage2d ();
+
+  virtual void setup (lay::Dispatcher *root);
+  virtual void commit (lay::Dispatcher *root);
+
+private:
+  Ui::LayoutViewConfigPage2d *mp_ui;
+};
+
+class LayoutViewConfigPage3a
   : public lay::ConfigPage
 {
 Q_OBJECT
diff --git a/src/laybasic/laybasic/layLayoutViewFunctions.cc b/src/laybasic/laybasic/layLayoutViewFunctions.cc
new file mode 100644
index 000000000..dc774dd26
--- /dev/null
+++ b/src/laybasic/laybasic/layLayoutViewFunctions.cc
@@ -0,0 +1,2256 @@
+
+/*
+
+  KLayout Layout Viewer
+  Copyright (C) 2006-2020 Matthias Koefferlein
+
+  This program is free software; you can redistribute it and/or modify
+  it under the terms of the GNU General Public License as published by
+  the Free Software Foundation; either version 2 of the License, or
+  (at your option) any later version.
+
+  This program is distributed in the hope that it will be useful,
+  but WITHOUT ANY WARRANTY; without even the implied warranty of
+  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+  GNU General Public License for more details.
+
+  You should have received a copy of the GNU General Public License
+  along with this program; if not, write to the Free Software
+  Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
+
+*/
+
+#include "layLayoutViewFunctions.h"
+#include "layLayoutView.h"
+#include "layCellSelectionForm.h"
+#include "layLayoutStatisticsForm.h"
+#include "layLayoutPropertiesForm.h"
+#include "layHierarchyControlPanel.h"
+#include "layLayerControlPanel.h"
+#include "layTipDialog.h"
+#include "laySelectCellViewForm.h"
+#include "layMove.h"
+#include "laybasicConfig.h"
+
+#include "dbClipboard.h"
+#include "dbRecursiveShapeIterator.h"
+#include "dbLayoutUtils.h"
+
+#include <QMessageBox>
+#include <QInputDialog>
+
+namespace lay
+{
+
+LayoutViewFunctions::LayoutViewFunctions (db::Manager *manager, LayoutView *view)
+  : lay::Plugin (view), mp_view (view), mp_manager (manager)
+{
+  m_del_cell_mode = 0;
+  m_move_to_origin_mode_x = 0;
+  m_move_to_origin_mode_y = 0;
+  m_del_cell_mode = 0;
+  m_layer_hier_mode = 0;
+  m_duplicate_hier_mode = 2;
+  m_clear_before = true;
+  m_copy_cva = -1;
+  m_copy_cvr = -1;
+  m_copy_layera = -1;
+  m_copy_layerr = -1;
+
+  m_new_layer_props.layer = 1;
+  m_new_layer_props.datatype = 0;
+}
+
+LayoutViewFunctions::~LayoutViewFunctions ()
+{
+  //  .. nothing yet..
+}
+
+void
+LayoutViewFunctions::menu_activated (const std::string &symbol)
+{
+  if (symbol == "cm_show_properties") {
+
+    view ()->show_properties (view ());
+
+  } else if (symbol == "cm_delete") {
+
+    view ()->del ();
+    //  because a "delete" might involve objects currently edited, we cancel the edit after we have deleted the object
+    view ()->cancel ();
+    view ()->clear_selection ();
+
+  } else if (symbol == "cm_unselect_all") {
+    view ()->select (db::DBox (), lay::Editable::Reset);
+  } else if (symbol == "cm_select_all") {
+    view ()->select (view ()->full_box (), lay::Editable::Replace);
+  } else if (symbol == "cm_select_next_item") {
+    view ()->repeat_selection (lay::Editable::Replace);
+  } else if (symbol == "cm_select_next_item_add") {
+    view ()->repeat_selection (lay::Editable::Add);
+  } else if (symbol == "cm_lv_paste") {
+    cm_layer_paste ();
+  } else if (symbol == "cm_lv_cut") {
+    cm_layer_cut ();
+  } else if (symbol == "cm_lv_copy") {
+    cm_layer_copy ();
+  } else if (symbol == "cm_cell_paste") {
+    cm_cell_paste ();
+  } else if (symbol == "cm_cell_cut") {
+    cm_cell_cut ();
+  } else if (symbol == "cm_cell_copy") {
+    cm_cell_copy ();
+  } else if (symbol == "cm_duplicate") {
+    do_cm_duplicate (false);
+  } else if (symbol == "cm_duplicate_interactive") {
+    do_cm_duplicate (true);
+  } else if (symbol == "cm_copy") {
+
+    view ()->copy ();
+    view ()->clear_selection ();
+
+  } else if (symbol == "cm_paste") {
+    do_cm_paste (false);
+  } else if (symbol == "cm_paste_interactive") {
+    do_cm_paste (true);
+  } else if (symbol == "cm_cut") {
+
+    view ()->cut ();
+    view ()->cancel (); //  see del() for reason why cancel is after cut
+    view ()->clear_selection ();
+
+  } else if (symbol == "cm_zoom_fit_sel") {
+    view ()->zoom_fit_sel ();
+  } else if (symbol == "cm_zoom_fit") {
+    view ()->zoom_fit ();
+  } else if (symbol == "cm_pan_left") {
+    view ()->pan_left ();
+  } else if (symbol == "cm_pan_right") {
+    view ()->pan_right ();
+  } else if (symbol == "cm_pan_up") {
+    view ()->pan_up ();
+  } else if (symbol == "cm_pan_down") {
+    view ()->pan_down ();
+  } else if (symbol == "cm_zoom_in") {
+    view ()->zoom_in ();
+  } else if (symbol == "cm_zoom_out") {
+    view ()->zoom_out ();
+  } else if (symbol == "cm_select_current_cell") {
+
+    if (view ()->active_cellview_index () >= 0) {
+      lay::LayoutView::cell_path_type path;
+      int cvi = view ()->active_cellview_index ();
+      view ()->current_cell_path (path);
+      view ()->select_cell_fit (path, cvi);
+    }
+
+  } else if (symbol == "cm_open_current_cell") {
+
+    if (view ()->active_cellview_index () >= 0) {
+      cm_open_current_cell ();
+    }
+
+  } else if (symbol == "cm_select_cell") {
+
+    if (view ()->active_cellview_index () >= 0) {
+
+      lay::CellSelectionForm form (0, view (), "cell_selection_form");
+
+      if (form.exec () == QDialog::Accepted &&
+          form.selected_cellview_index () >= 0) {
+        view ()->select_cell (form.selected_cellview ().combined_unspecific_path (), form.selected_cellview_index ());
+        view ()->set_current_cell_path (form.selected_cellview_index (), form.selected_cellview ().combined_unspecific_path ());
+        view ()->zoom_fit ();
+      }
+
+    }
+
+  } else if (symbol == "cm_new_cell") {
+    cm_new_cell ();
+  } else if (symbol == "cm_adjust_origin") {
+    if (view ()->active_cellview_index () >= 0) {
+      cm_align_cell_origin ();
+    }
+  } else if (symbol == "cm_cell_convert_to_static") {
+    if (view ()->active_cellview_index () >= 0) {
+      cm_cell_convert_to_static ();
+    }
+  } else if (symbol == "cm_lay_convert_to_static") {
+    if (view ()->active_cellview_index () >= 0) {
+      cm_lay_convert_to_static ();
+    }
+  } else if (symbol == "cm_lay_move") {
+    if (view ()->active_cellview_index () >= 0) {
+      cm_lay_move ();
+    }
+  } else if (symbol == "cm_lay_scale") {
+    if (view ()->active_cellview_index () >= 0) {
+      cm_lay_scale ();
+    }
+  } else if (symbol == "cm_lay_free_rot") {
+    if (view ()->active_cellview_index () >= 0) {
+      cm_lay_free_rot ();
+    }
+  } else if (symbol == "cm_lay_rot_ccw") {
+    if (view ()->active_cellview_index () >= 0) {
+      cm_lay_rot_ccw ();
+    }
+  } else if (symbol == "cm_lay_rot_cw") {
+    if (view ()->active_cellview_index () >= 0) {
+      cm_lay_rot_cw ();
+    }
+  } else if (symbol == "cm_lay_flip_y") {
+    if (view ()->active_cellview_index () >= 0) {
+      cm_lay_flip_y ();
+    }
+  } else if (symbol == "cm_lay_flip_x") {
+    if (view ()->active_cellview_index () >= 0) {
+      cm_lay_flip_x ();
+    }
+  } else if (symbol == "cm_sel_move") {
+    if (view ()->active_cellview_index () >= 0) {
+      cm_sel_move ();
+    }
+  } else if (symbol == "cm_sel_move_to") {
+    if (view ()->active_cellview_index () >= 0) {
+      cm_sel_move_to ();
+    }
+  } else if (symbol == "cm_sel_move_interactive") {
+    if (view ()->active_cellview_index () >= 0) {
+      cm_sel_move_interactive ();
+    }
+  } else if (symbol == "cm_sel_scale") {
+    if (view ()->active_cellview_index () >= 0) {
+      cm_sel_scale ();
+    }
+  } else if (symbol == "cm_sel_free_rot") {
+    if (view ()->active_cellview_index () >= 0) {
+      cm_sel_free_rot ();
+    }
+  } else if (symbol == "cm_sel_rot_ccw") {
+    if (view ()->active_cellview_index () >= 0) {
+      cm_sel_rot_ccw ();
+    }
+  } else if (symbol == "cm_sel_rot_cw") {
+    if (view ()->active_cellview_index () >= 0) {
+      cm_sel_rot_cw ();
+    }
+  } else if (symbol == "cm_sel_flip_y") {
+    if (view ()->active_cellview_index () >= 0) {
+      cm_sel_flip_y ();
+    }
+  } else if (symbol == "cm_sel_flip_x") {
+    if (view ()->active_cellview_index () >= 0) {
+      cm_sel_flip_x ();
+    }
+  } else if (symbol == "cm_edit_layer") {
+    if (view ()->active_cellview_index () >= 0) {
+      cm_edit_layer ();
+    }
+  } else if (symbol == "cm_delete_layer") {
+    if (view ()->active_cellview_index () >= 0) {
+      cm_delete_layer ();
+    }
+  } else if (symbol == "cm_clear_layer") {
+    if (view ()->active_cellview_index () >= 0) {
+      cm_clear_layer ();
+    }
+  } else if (symbol == "cm_copy_layer") {
+    if (view ()->active_cellview_index () >= 0) {
+      cm_copy_layer ();
+    }
+  } else if (symbol == "cm_new_layer") {
+    if (view ()->active_cellview_index () >= 0) {
+      cm_new_layer ();
+    }
+  } else if (symbol == "cm_layout_props") {
+    lay::LayoutPropertiesForm lp_form (view (), view (), "layout_props_form");
+    lp_form.exec ();
+  } else if (symbol == "cm_layout_stats") {
+    lay::LayoutStatisticsForm lp_form (view (), view (), "layout_props_form");
+    lp_form.exec ();
+  } else if (symbol == "cm_reload") {
+    cm_reload ();
+  } else if (symbol == "cm_inc_max_hier") {
+    int new_to = view ()->get_max_hier_levels () + 1;
+    view ()->set_hier_levels (std::make_pair (view ()->get_min_hier_levels (), new_to));
+  } else if (symbol == "cm_dec_max_hier") {
+    int new_to = view ()->get_max_hier_levels () > 0 ? view ()->get_max_hier_levels () - 1 : 0;
+    view ()->set_hier_levels (std::make_pair (std::min (view ()->get_min_hier_levels (), new_to), new_to));
+  } else if (symbol == "cm_max_hier") {
+    view ()->max_hier ();
+  } else if (symbol == "cm_max_hier_0") {
+    view ()->set_hier_levels (std::make_pair (std::min (view ()->get_min_hier_levels (), 0), 0));
+  } else if (symbol == "cm_max_hier_1") {
+    view ()->set_hier_levels (std::make_pair (std::min (view ()->get_min_hier_levels (), 0), 1));
+  } else if (symbol == "cm_prev_display_state") {
+    if (view ()->has_prev_display_state ()) {
+      view ()->prev_display_state ();
+    }
+  } else if (symbol == "cm_next_display_state") {
+    if (view ()->has_next_display_state ()) {
+      view ()->next_display_state ();
+    }
+  } else if (symbol == "cm_redraw") {
+    view ()->redraw ();
+  } else if (symbol == "cm_cell_delete") {
+    cm_cell_delete ();
+  } else if (symbol == "cm_cell_replace") {
+    cm_cell_replace ();
+  } else if (symbol == "cm_cell_rename") {
+    cm_cell_rename ();
+  } else if (symbol == "cm_cell_flatten") {
+    cm_cell_flatten ();
+  } else if (symbol == "cm_cell_select") {
+    cm_cell_select ();
+  } else if (symbol == "cm_cell_hide") {
+    cm_cell_hide ();
+  } else if (symbol == "cm_cell_show") {
+    cm_cell_show ();
+  } else if (symbol == "cm_cell_show_all") {
+    cm_cell_show_all ();
+  } else if (symbol == "cm_cell_user_properties") {
+    if (view ()->active_cellview_index () >= 0) {
+      cm_cell_user_properties ();
+    }
+  } else if (symbol == "cm_lv_select_all") {
+    cm_select_all ();
+  } else if (symbol == "cm_lv_new_tab") {
+    cm_new_tab ();
+  } else if (symbol == "cm_lv_rename_tab") {
+    cm_rename_tab ();
+  } else if (symbol == "cm_lv_make_invalid") {
+    cm_make_invalid ();
+  } else if (symbol == "cm_lv_remove_tab") {
+    cm_remove_tab ();
+  } else if (symbol == "cm_lv_make_valid") {
+    cm_make_valid ();
+  } else if (symbol == "cm_lv_hide_all") {
+    cm_hide_all ();
+  } else if (symbol == "cm_lv_hide") {
+    cm_hide ();
+  } else if (symbol == "cm_lv_show_only") {
+    cm_show_only ();
+  } else if (symbol == "cm_lv_show_all") {
+    cm_show_all ();
+  } else if (symbol == "cm_lv_show") {
+    cm_show ();
+  } else if (symbol == "cm_lv_rename") {
+    cm_rename ();
+  } else if (symbol == "cm_lv_delete") {
+    cm_delete ();
+  } else if (symbol == "cm_lv_insert") {
+    cm_insert ();
+  } else if (symbol == "cm_lv_group") {
+    cm_group ();
+  } else if (symbol == "cm_lv_ungroup") {
+    cm_ungroup ();
+  } else if (symbol == "cm_lv_source") {
+    cm_source ();
+  } else if (symbol == "cm_lv_sort_by_name") {
+    cm_sort_by_name ();
+  } else if (symbol == "cm_lv_sort_by_ild") {
+    cm_sort_by_ild ();
+  } else if (symbol == "cm_lv_sort_by_idl") {
+    cm_sort_by_idl ();
+  } else if (symbol == "cm_lv_sort_by_ldi") {
+    cm_sort_by_ldi ();
+  } else if (symbol == "cm_lv_sort_by_dli") {
+    cm_sort_by_dli ();
+  } else if (symbol == "cm_lv_regroup_by_index") {
+    cm_regroup_by_index ();
+  } else if (symbol == "cm_lv_regroup_by_datatype") {
+    cm_regroup_by_datatype ();
+  } else if (symbol == "cm_lv_regroup_by_layer") {
+    cm_regroup_by_layer ();
+  } else if (symbol == "cm_lv_regroup_flatten") {
+    cm_regroup_flatten ();
+  } else if (symbol == "cm_lv_expand_all") {
+    cm_expand_all ();
+  } else if (symbol == "cm_lv_add_missing") {
+    cm_add_missing ();
+  } else if (symbol == "cm_lv_remove_unused") {
+    cm_remove_unused ();
+  }
+}
+
+void
+LayoutViewFunctions::cm_cell_user_properties ()
+{
+  if (! view ()->hierarchy_panel ()) {
+    return;
+  }
+
+  int cv_index = view ()->active_cellview_index ();
+  lay::LayoutView::cell_path_type path;
+  view ()->hierarchy_panel ()->current_cell (cv_index, path);
+
+  if (cv_index >= 0 && path.size () > 0) {
+
+    db::Layout &layout = view ()->cellview (cv_index)->layout ();
+    db::Cell &cell = layout.cell (path.back ());
+    db::properties_id_type prop_id = cell.prop_id ();
+
+    lay::UserPropertiesForm props_form (view ());
+    if (props_form.show (view (), cv_index, prop_id)) {
+
+      view ()->transaction (tl::to_string (QObject::tr ("Edit cell's user propertes")));
+      cell.prop_id (prop_id);
+      view ()->commit ();
+
+    }
+
+  }
+}
+
+void
+LayoutViewFunctions::cm_cell_replace ()
+{
+  if (! view ()->hierarchy_panel ()) {
+    return;
+  }
+
+  int cv_index = view ()->active_cellview_index ();
+  std::vector<lay::LayoutView::cell_path_type> paths;
+  view ()->hierarchy_panel ()->selected_cells (cv_index, paths);
+
+  if (cv_index >= 0 && paths.size () > 0) {
+
+    if (paths.size () > 1) {
+      throw tl::Exception (tl::to_string (QObject::tr ("Replace cell cannot be used when multiple cells are selected")));
+    }
+
+    db::Layout &layout = view ()->cellview (cv_index)->layout ();
+
+    bool needs_to_ask = false;
+    for (std::vector<lay::LayoutView::cell_path_type>::const_iterator p = paths.begin (); p != paths.end () && ! needs_to_ask; ++p) {
+      if (layout.is_valid_cell_index (p->back ()) && ! layout.cell (p->back ()).is_leaf ()) {
+        needs_to_ask = true;
+      }
+    }
+
+
+    lay::ReplaceCellOptionsDialog mode_dialog (view ());
+
+    db::cell_index_type with_cell = paths.front ().back ();
+    int mode = needs_to_ask ? m_del_cell_mode : 0;
+
+    if (mode_dialog.exec_dialog (view ()->cellview (cv_index), mode, with_cell)) {
+
+      if (needs_to_ask) {
+        m_del_cell_mode = mode;
+      }
+
+      if (with_cell != paths.front ().back ()) {
+
+        //  remember the current path
+        lay::LayoutView::cell_path_type cell_path (view ()->cellview (cv_index).combined_unspecific_path ());
+
+        view ()->clear_selection ();
+
+        view ()->transaction (tl::to_string (QObject::tr ("Replace cells")));
+
+        //  replace instances of the target cell with the new cell 
+
+        db::Cell &target_cell = layout.cell (paths.front ().back ());
+
+        std::vector<std::pair<db::cell_index_type, db::Instance> > parents;
+        for (db::Cell::parent_inst_iterator pi = target_cell.begin_parent_insts (); ! pi.at_end (); ++pi) {
+          parents.push_back (std::make_pair (pi->parent_cell_index (), pi->child_inst ()));
+        }
+
+        for (std::vector<std::pair<db::cell_index_type, db::Instance> >::const_iterator p = parents.begin (); p != parents.end (); ++p) {
+          db::CellInstArray ia = p->second.cell_inst ();
+          ia.object ().cell_index (with_cell);
+          layout.cell (p->first).replace (p->second, ia);
+        }
+
+        std::set<db::cell_index_type> cells_to_delete;
+        for (std::vector<lay::LayoutView::cell_path_type>::const_iterator p = paths.begin (); p != paths.end (); ++p) {
+          if (! p->empty () && layout.is_valid_cell_index (p->back ())) {
+            cells_to_delete.insert (p->back ());
+            if (mode == 2) {
+              layout.cell (p->back ()).collect_called_cells (cells_to_delete);
+            }
+          }
+        }
+
+        //  support a propagation use case:
+        std::set<db::cell_index_type> cells_below_replacement_cell;
+        cells_below_replacement_cell.insert (with_cell);
+        layout.cell (with_cell).collect_called_cells (cells_below_replacement_cell);
+        for (std::set<db::cell_index_type>::const_iterator c = cells_below_replacement_cell.begin (); c != cells_below_replacement_cell.end (); ++c) {
+          cells_to_delete.erase (*c);
+        }
+
+        if (mode == 0 || mode == 2) {
+          layout.delete_cells (cells_to_delete);
+        } else if (mode == 1) {
+          layout.prune_cells (cells_to_delete);
+        }
+
+        layout.cleanup ();
+
+        view ()->commit ();
+
+        //  If one of the cells in the path was deleted, establish a valid path
+
+        bool needs_update = false;
+        for (size_t i = cell_path.size (); i > 0; ) {
+          --i;
+          if (! layout.is_valid_cell_index (cell_path [i])) {
+            cell_path.erase (cell_path.begin () + i, cell_path.end ());
+            needs_update = true;
+          }
+        }
+
+        if (needs_update) {
+          view ()->select_cell (cell_path, cv_index);
+        }
+
+      }
+
+    }
+
+  }
+}
+
+void
+LayoutViewFunctions::cm_lay_convert_to_static ()
+{
+  //  end move operations, cancel edit operations
+  view ()->cancel_edits ();
+  view ()->clear_selection ();
+
+  int cv_index = view ()->active_cellview_index ();
+  if (cv_index >= 0) {
+
+    db::Layout &layout = view ()->cellview (cv_index)->layout ();
+
+    view ()->transaction (tl::to_string (QObject::tr ("Convert all cells to static")));
+
+    std::vector<db::cell_index_type> cells;
+    for (db::Layout::const_iterator c = layout.begin (); c != layout.end (); ++c) {
+      cells.push_back (c->cell_index ());
+    }
+
+    std::map<db::cell_index_type, db::cell_index_type> cell_map;
+    for (std::vector<db::cell_index_type>::const_iterator c = cells.begin (); c != cells.end (); ++c) {
+      if (layout.is_valid_cell_index (*c)) {
+        db::cell_index_type new_cell = layout.convert_cell_to_static (*c);
+        if (new_cell != *c) {
+          cell_map.insert (std::make_pair (*c, new_cell));
+        }
+      }
+    }
+
+    //  rewrite instances
+    for (db::Layout::iterator c = layout.begin (); c != layout.end (); ++c) {
+      for (db::Cell::const_iterator i = c->begin (); ! i.at_end (); ++i) {
+        std::map<db::cell_index_type, db::cell_index_type>::const_iterator cm = cell_map.find (i->cell_index ());
+        if (cm != cell_map.end ()) {
+          db::CellInstArray ci = i->cell_inst ();
+          ci.object ().cell_index (cm->second);
+          c->replace (*i, ci);
+        }
+      }
+    }
+
+    layout.cleanup ();
+
+    view ()->commit ();
+
+  }
+}
+
+void
+LayoutViewFunctions::cm_cell_convert_to_static ()
+{
+  if (! view ()->hierarchy_panel ()) {
+    return;
+  }
+
+  int cv_index = view ()->active_cellview_index ();
+  std::vector<lay::LayoutView::cell_path_type> paths;
+  view ()->hierarchy_panel ()->selected_cells (cv_index, paths);
+
+  if (cv_index >= 0 && paths.size () > 0) {
+
+    db::Layout &layout = view ()->cellview (cv_index)->layout ();
+
+    //  remember the current path
+    lay::LayoutView::cell_path_type cell_path (view ()->cellview (cv_index).combined_unspecific_path ());
+
+    view ()->clear_selection ();
+
+    view ()->transaction (tl::to_string (QObject::tr ("Convert cells to static")));
+
+    std::map<db::cell_index_type, db::cell_index_type> cell_map;
+
+    for (std::vector<lay::LayoutView::cell_path_type>::iterator p = paths.begin (); p != paths.end (); ++p) {
+      if (! p->empty () && layout.is_valid_cell_index (p->back ())) {
+        db::cell_index_type new_cell = layout.convert_cell_to_static (p->back ());
+        if (new_cell != p->back ()) {
+          cell_map.insert (std::make_pair (p->back (), new_cell));
+          p->back () = new_cell;
+        }
+      }
+    }
+
+    //  rewrite instances
+    for (db::Layout::iterator c = layout.begin (); c != layout.end (); ++c) {
+      for (db::Cell::const_iterator i = c->begin (); ! i.at_end (); ++i) {
+        std::map<db::cell_index_type, db::cell_index_type>::const_iterator cm = cell_map.find (i->cell_index ());
+        if (cm != cell_map.end ()) {
+          db::CellInstArray ci = i->cell_inst ();
+          ci.object ().cell_index (cm->second);
+          c->replace (*i, ci);
+        }
+      }
+    }
+
+    layout.cleanup ();
+
+    view ()->commit ();
+
+    //  If one of the cells in the path was deleted, establish a valid path
+
+    bool needs_update = false;
+    for (size_t i = cell_path.size (); i > 0; ) {
+      --i;
+      if (! layout.is_valid_cell_index (cell_path [i])) {
+        cell_path.erase (cell_path.begin () + i, cell_path.end ());
+        needs_update = true;
+      }
+    }
+
+    if (needs_update) {
+      view ()->select_cell (cell_path, cv_index);
+    }
+
+  }
+}
+
+static void
+collect_cells_to_delete (const db::Layout &layout, const db::Cell &cell, std::set<db::cell_index_type> &called)
+{
+  //  don't delete proxies - they are deleted later when the layout is cleaned
+  for (db::Cell::child_cell_iterator cc = cell.begin_child_cells (); ! cc.at_end (); ++cc) {
+    if (called.find (*cc) == called.end () && !layout.cell (*cc).is_proxy ()) {
+      called.insert (*cc);
+      collect_cells_to_delete (layout, layout.cell (*cc), called);
+    }
+  }
+}
+
+void
+LayoutViewFunctions::cm_cell_delete ()
+{
+  if (! view ()->hierarchy_panel ()) {
+    return;
+  }
+
+  int cv_index = view ()->active_cellview_index ();
+  std::vector<lay::LayoutView::cell_path_type> paths;
+  view ()->hierarchy_panel ()->selected_cells (cv_index, paths);
+
+  if (cv_index >= 0 && paths.size () > 0) {
+
+    db::Layout &layout = view ()->cellview (cv_index)->layout ();
+
+    bool needs_to_ask = false;
+    for (std::vector<lay::LayoutView::cell_path_type>::const_iterator p = paths.begin (); p != paths.end () && ! needs_to_ask; ++p) {
+      if (layout.is_valid_cell_index (p->back ()) && ! layout.cell (p->back ()).is_leaf ()) {
+        needs_to_ask = true;
+      }
+    }
+
+    int mode = m_del_cell_mode;
+    if (! needs_to_ask) {
+      mode = 0;
+    }
+
+    lay::DeleteCellModeDialog mode_dialog (view ());
+    if (! needs_to_ask || mode_dialog.exec_dialog (mode)) {
+
+      if (needs_to_ask) {
+        m_del_cell_mode = mode;
+      }
+
+      //  remember the current path
+      lay::LayoutView::cell_path_type cell_path (view ()->cellview (cv_index).combined_unspecific_path ());
+
+      view ()->clear_selection ();
+
+      std::set<db::cell_index_type> cells_to_delete;
+      for (std::vector<lay::LayoutView::cell_path_type>::const_iterator p = paths.begin (); p != paths.end (); ++p) {
+        if (! p->empty () && layout.is_valid_cell_index (p->back ())) {
+          cells_to_delete.insert (p->back ());
+          if (mode == 2) {
+            collect_cells_to_delete (layout, layout.cell (p->back ()), cells_to_delete);
+          }
+        }
+      }
+
+      view ()->transaction (tl::to_string (QObject::tr ("Delete cells")));
+
+      if (mode == 0 || mode == 2) {
+        layout.delete_cells (cells_to_delete);
+      } else if (mode == 1) {
+        layout.prune_cells (cells_to_delete);
+      }
+
+      layout.cleanup ();
+
+      view ()->commit ();
+
+      //  If one of the cells in the path was deleted, establish a valid path
+
+      bool needs_update = false;
+      for (size_t i = cell_path.size (); i > 0; ) {
+        --i;
+        if (! layout.is_valid_cell_index (cell_path [i])) {
+          cell_path.erase (cell_path.begin () + i, cell_path.end ());
+          needs_update = true;
+        }
+      }
+
+      if (needs_update) {
+        view ()->select_cell (cell_path, cv_index);
+      }
+
+    }
+
+  }
+}
+
+void 
+LayoutViewFunctions::cm_layer_copy ()
+{
+  if (view ()->control_panel ()) {
+    view ()->control_panel ()->copy ();
+  }
+}
+
+void 
+LayoutViewFunctions::cm_layer_cut ()
+{
+  if (view ()->control_panel ()) {
+    db::Transaction trans (manager (), tl::to_string (QObject::tr ("Cut Layers")));
+    view ()->control_panel ()->cut ();
+  }
+}
+
+void 
+LayoutViewFunctions::cm_layer_paste ()
+{
+  if (view ()->control_panel ()) {
+    db::Transaction trans (manager (), tl::to_string (QObject::tr ("Paste Layers")));
+    view ()->control_panel ()->paste ();
+  }
+}
+
+void
+LayoutViewFunctions::cm_cell_cut ()
+{
+  if (view ()->hierarchy_panel ()) {
+    //  TODO: currently the hierarchy panel's cut function does it's own transaction handling.
+    //  Otherwise the cut function is not working propertly.
+    view ()->hierarchy_panel ()->cut ();
+  }
+}
+
+void
+LayoutViewFunctions::cm_cell_paste ()
+{
+  if (view ()->hierarchy_panel ()) {
+    db::Transaction trans (manager (), tl::to_string (QObject::tr ("Paste Cells")));
+    view ()->hierarchy_panel ()->paste ();
+  }
+}
+
+void
+LayoutViewFunctions::cm_cell_copy ()
+{
+  if (view ()->hierarchy_panel ()) {
+    view ()->hierarchy_panel ()->copy ();
+  }
+}
+
+void
+LayoutViewFunctions::cm_cell_flatten ()
+{
+  if (! view ()->hierarchy_panel ()) {
+    return;
+  }
+
+  tl_assert (view ()->is_editable ());
+
+  int cv_index = view ()->active_cellview_index ();
+  if (cv_index >= 0) {
+
+    const lay::CellView &cv = view ()->cellview (cv_index);
+    if (cv.is_valid ()) {
+
+      std::vector<HierarchyControlPanel::cell_path_type> paths;
+      view ()->hierarchy_panel ()->selected_cells (cv_index, paths);
+      if (paths.empty ()) {
+        throw tl::Exception (tl::to_string (QObject::tr ("No cells selected for flattening")));
+      }
+
+      for (std::vector<HierarchyControlPanel::cell_path_type>::const_iterator p = paths.begin (); p != paths.end (); ++p) {
+        if (p->size () > 0 && cv->layout ().cell (p->back ()).is_proxy ()) {
+          throw tl::Exception (tl::to_string (QObject::tr ("Cannot use this function on a PCell or library cell")));
+        }
+      }
+
+      FlattenInstOptionsDialog options_dialog (view ());
+
+      int flatten_insts_levels = -1;
+      bool prune = true;
+      if (options_dialog.exec_dialog (flatten_insts_levels, prune) && flatten_insts_levels != 0) {
+
+        bool supports_undo = true;
+
+        if (manager () && manager ()->is_enabled ()) {
+
+          lay::TipDialog td (QApplication::activeWindow (), 
+                             tl::to_string (QObject::tr ("Undo buffering for the following operation can be memory and time consuming.\nChoose \"Yes\" to use undo buffering or \"No\" for no undo buffering. Warning: in the latter case, the undo history will be lost.\n\nChoose undo buffering?")), 
+                             "flatten-undo-buffering",
+                             lay::TipDialog::yesnocancel_buttons);
+
+          lay::TipDialog::button_type button = lay::TipDialog::null_button;
+          td.exec_dialog (button);
+          if (button == lay::TipDialog::cancel_button) {
+            return;
+          }
+
+          supports_undo = (button == lay::TipDialog::yes_button);
+
+        } else {
+          supports_undo = false;
+        }
+
+        view ()->cancel_edits ();
+        view ()->clear_selection ();
+
+        if (manager ()) {
+          if (! supports_undo) {
+            manager ()->clear ();
+          } else {
+            manager ()->transaction (tl::to_string (QObject::tr ("Flatten cell")));
+          }
+        }
+
+        db::Layout &layout = cv->layout ();
+
+        std::set<db::cell_index_type> child_cells;
+        for (std::vector<HierarchyControlPanel::cell_path_type>::const_iterator p = paths.begin (); p != paths.end (); ++p) {
+          if (p->size () > 0) {
+            layout.cell (p->back ()).collect_called_cells (child_cells);
+          }
+        }
+
+        //  don't flatten cells which are child cells of the cells to flatten
+        std::set<db::cell_index_type> cells_to_flatten;
+        for (std::vector<HierarchyControlPanel::cell_path_type>::const_iterator p = paths.begin (); p != paths.end (); ++p) {
+          if (p->size () > 0 && child_cells.find (p->back ()) == child_cells.end ()) {
+            cells_to_flatten.insert (p->back ());
+          }
+        }
+
+        for (std::set<db::cell_index_type>::const_iterator c = cells_to_flatten.begin (); c != cells_to_flatten.end (); ++c) {
+          db::Cell &target_cell = layout.cell (*c);
+          layout.flatten (target_cell, flatten_insts_levels, prune);
+        }
+
+        layout.cleanup ();
+
+        if (supports_undo && manager ()) {
+          manager ()->commit ();
+        }
+
+      }
+
+    }
+
+  }
+}
+
+void
+LayoutViewFunctions::cm_cell_rename ()
+{
+  if (! view ()->hierarchy_panel ()) {
+    return;
+  }
+
+  int cv_index = view ()->active_cellview_index ();
+  lay::LayoutView::cell_path_type path;
+  view ()->hierarchy_panel ()->current_cell (cv_index, path);
+
+  if (cv_index >= 0 && path.size () > 0) {
+
+    lay::RenameCellDialog name_dialog (view ());
+
+    db::Layout &layout = view ()->cellview (cv_index)->layout ();
+    std::string name (layout.cell_name (path.back ()));
+    if (name_dialog.exec_dialog (layout, name)) {
+
+      view ()->transaction (tl::to_string (QObject::tr ("Rename cell")));
+      layout.rename_cell (path.back (), name.c_str ());
+      view ()->commit ();
+
+    }
+
+  }
+}
+
+void
+LayoutViewFunctions::cm_cell_select ()
+{
+  if (view ()->hierarchy_panel ()) {
+    view ()->hierarchy_panel ()->cm_cell_select ();
+  }
+}
+
+void
+LayoutViewFunctions::cm_open_current_cell ()
+{
+  view ()->set_current_cell_path (view ()->active_cellview_index (), view ()->cellview (view ()->active_cellview_index ()).combined_unspecific_path ());
+}
+
+void
+LayoutViewFunctions::cm_cell_hide ()
+{
+  if (view ()->hierarchy_panel ()) {
+
+    std::vector<HierarchyControlPanel::cell_path_type> paths;
+    view ()->hierarchy_panel ()->selected_cells (view ()->active_cellview_index (), paths);
+
+    view ()->transaction (tl::to_string (QObject::tr ("Hide cell")));
+
+    for (std::vector<HierarchyControlPanel::cell_path_type>::const_iterator p = paths.begin (); p != paths.end (); ++p) {
+      if (! p->empty ()) {
+        view ()->hide_cell (p->back (), view ()->active_cellview_index ());
+      }
+    }
+
+    view ()->commit ();
+
+  }
+}
+
+void
+LayoutViewFunctions::cm_cell_show ()
+{
+  if (view ()->hierarchy_panel ()) {
+
+    std::vector<HierarchyControlPanel::cell_path_type> paths;
+    view ()->hierarchy_panel ()->selected_cells (view ()->active_cellview_index (), paths);
+
+    view ()->transaction (tl::to_string (QObject::tr ("Show cell")));
+
+    for (std::vector<HierarchyControlPanel::cell_path_type>::const_iterator p = paths.begin (); p != paths.end (); ++p) {
+      if (! p->empty ()) {
+        view ()->show_cell (p->back (), view ()->active_cellview_index ());
+      }
+    }
+
+    view ()->commit ();
+
+  }
+}
+
+void
+LayoutViewFunctions::cm_cell_show_all ()
+{
+  if (view ()->hierarchy_panel ()) {
+    view ()->transaction (tl::to_string (QObject::tr ("Show all cells")));
+    view ()->show_all_cells ();
+    view ()->commit ();
+  }
+}
+
+void
+LayoutViewFunctions::cm_select_all ()
+{
+  if (view ()->control_panel ()) {
+    view ()->control_panel ()->cm_select_all ();
+  }
+}
+
+void
+LayoutViewFunctions::cm_new_tab ()
+{
+  if (view ()->control_panel ()) {
+    view ()->control_panel ()->cm_new_tab ();
+  }
+}
+
+void
+LayoutViewFunctions::cm_remove_tab ()
+{
+  if (view ()->control_panel ()) {
+    view ()->control_panel ()->cm_remove_tab ();
+  }
+}
+
+void
+LayoutViewFunctions::cm_rename_tab ()
+{
+  if (view ()->control_panel ()) {
+    view ()->control_panel ()->cm_rename_tab ();
+  }
+}
+
+void
+LayoutViewFunctions::cm_make_invalid ()
+{
+  if (view ()->control_panel ()) {
+    view ()->control_panel ()->cm_make_invalid ();
+  }
+}
+
+void
+LayoutViewFunctions::cm_make_valid ()
+{
+  if (view ()->control_panel ()) {
+    view ()->control_panel ()->cm_make_valid ();
+  }
+}
+
+void
+LayoutViewFunctions::cm_hide ()
+{
+  if (view ()->control_panel ()) {
+    view ()->control_panel ()->cm_hide ();
+  }
+}
+
+void
+LayoutViewFunctions::cm_hide_all ()
+{
+  if (view ()->control_panel ()) {
+    view ()->control_panel ()->cm_hide_all ();
+  }
+}
+
+void
+LayoutViewFunctions::cm_show_only ()
+{
+  if (view ()->control_panel ()) {
+    view ()->control_panel ()->cm_show_only ();
+  }
+}
+
+void
+LayoutViewFunctions::cm_show_all ()
+{
+  if (view ()->control_panel ()) {
+    view ()->control_panel ()->cm_show_all ();
+  }
+}
+
+void
+LayoutViewFunctions::cm_show ()
+{
+  if (view ()->control_panel ()) {
+    view ()->control_panel ()->cm_show ();
+  }
+}
+
+void
+LayoutViewFunctions::cm_rename ()
+{
+  if (view ()->control_panel ()) {
+    view ()->control_panel ()->cm_rename ();
+  }
+}
+
+void
+LayoutViewFunctions::cm_delete ()
+{
+  if (view ()->control_panel ()) {
+    view ()->control_panel ()->cm_delete ();
+  }
+}
+
+void
+LayoutViewFunctions::cm_insert ()
+{
+  if (view ()->control_panel ()) {
+    view ()->control_panel ()->cm_insert ();
+  }
+}
+
+void
+LayoutViewFunctions::cm_group ()
+{
+  if (view ()->control_panel ()) {
+    view ()->control_panel ()->cm_group ();
+  }
+}
+
+void
+LayoutViewFunctions::cm_ungroup ()
+{
+  if (view ()->control_panel ()) {
+    view ()->control_panel ()->cm_ungroup ();
+  }
+}
+
+void
+LayoutViewFunctions::cm_source ()
+{
+  if (view ()->control_panel ()) {
+    view ()->control_panel ()->cm_source ();
+  }
+}
+
+void
+LayoutViewFunctions::cm_sort_by_name ()
+{
+  if (view ()->control_panel ()) {
+    view ()->control_panel ()->cm_sort_by_name ();
+  }
+}
+
+void
+LayoutViewFunctions::cm_sort_by_ild ()
+{
+  if (view ()->control_panel ()) {
+    view ()->control_panel ()->cm_sort_by_ild ();
+  }
+}
+
+void
+LayoutViewFunctions::cm_sort_by_idl ()
+{
+  if (view ()->control_panel ()) {
+    view ()->control_panel ()->cm_sort_by_idl ();
+  }
+}
+
+void
+LayoutViewFunctions::cm_sort_by_ldi ()
+{
+  if (view ()->control_panel ()) {
+    view ()->control_panel ()->cm_sort_by_ldi ();
+  }
+}
+
+void
+LayoutViewFunctions::cm_sort_by_dli ()
+{
+  if (view ()->control_panel ()) {
+    view ()->control_panel ()->cm_sort_by_dli ();
+  }
+}
+
+void
+LayoutViewFunctions::cm_regroup_by_index ()
+{
+  if (view ()->control_panel ()) {
+    view ()->control_panel ()->cm_regroup_by_index ();
+  }
+}
+
+void
+LayoutViewFunctions::cm_regroup_by_datatype ()
+{
+  if (view ()->control_panel ()) {
+    view ()->control_panel ()->cm_regroup_by_datatype ();
+  }
+}
+
+void
+LayoutViewFunctions::cm_regroup_by_layer ()
+{
+  if (view ()->control_panel ()) {
+    view ()->control_panel ()->cm_regroup_by_layer ();
+  }
+}
+
+void
+LayoutViewFunctions::cm_regroup_flatten ()
+{
+  if (view ()->control_panel ()) {
+    view ()->control_panel ()->cm_regroup_flatten ();
+  }
+}
+
+void
+LayoutViewFunctions::cm_expand_all ()
+{
+  if (view ()->control_panel ()) {
+    view ()->control_panel ()->cm_expand_all ();
+  }
+}
+
+void
+LayoutViewFunctions::cm_add_missing ()
+{
+  if (view ()->control_panel ()) {
+    view ()->control_panel ()->cm_add_missing ();
+  }
+}
+
+void
+LayoutViewFunctions::cm_remove_unused ()
+{
+  view ()->remove_unused_layers ();
+}
+
+void
+LayoutViewFunctions::do_cm_duplicate (bool interactive)
+{
+  //  Do duplicate simply by concatenating copy & paste currently.
+  //  Save the clipboard state before in order to preserve the current content
+  db::Clipboard saved_clipboard;
+  db::Clipboard::instance ().swap (saved_clipboard);
+
+  try {
+    view ()->copy ();
+    view ()->clear_selection ();
+    view ()->cancel ();
+    if (interactive) {
+      view ()->paste_interactive ();
+    } else {
+      view ()->paste ();
+    }
+    db::Clipboard::instance ().swap (saved_clipboard);
+  } catch (...) {
+    db::Clipboard::instance ().swap (saved_clipboard);
+    throw;
+  }
+}
+
+void
+LayoutViewFunctions::do_cm_paste (bool interactive)
+{
+  if (! db::Clipboard::instance ().empty ()) {
+    view ()->cancel ();
+    view ()->clear_selection ();
+    if (interactive) {
+      view ()->paste_interactive ();
+    } else {
+      view ()->paste ();
+    }
+  }
+}
+
+void
+LayoutViewFunctions::cm_new_cell ()
+{
+  static double s_new_cell_window_size = 2.0;
+  static std::string s_new_cell_cell_name;
+
+  NewCellPropertiesDialog cell_prop_dia (view ());
+  if (cell_prop_dia.exec_dialog (& view ()->cellview (view ()->active_cellview_index ())->layout (), s_new_cell_cell_name, s_new_cell_window_size)) {
+
+    db::cell_index_type new_ci = view ()->new_cell (view ()->active_cellview_index (), s_new_cell_cell_name.c_str ());
+    view ()->select_cell (new_ci, view ()->active_cellview_index ());
+
+    db::DBox zb = db::DBox (-0.5 * s_new_cell_window_size, -0.5 * s_new_cell_window_size, 0.5 * s_new_cell_window_size, 0.5 * s_new_cell_window_size);
+    if (view ()->get_max_hier_levels () < 1 || view ()->get_min_hier_levels () > 0) {
+      view ()->zoom_box_and_set_hier_levels (zb, std::make_pair (0, 1));
+    } else {
+      view ()->zoom_box (zb);
+    }
+
+  }
+}
+
+//  TODO: this constant is defined in MainWindow.cc too ...
+const int max_dirty_files = 15;
+
+void
+LayoutViewFunctions::cm_reload ()
+{
+  std::vector <int> selected;
+
+  if (view ()->cellviews () > 1) {
+
+    lay::SelectCellViewForm form (0, view (), tl::to_string (QObject::tr ("Select Layouts To Reload")));
+    form.select_all ();
+
+    if (form.exec () == QDialog::Accepted) {
+      selected = form.selected_cellviews ();
+    }
+
+  } else if (view ()->cellviews () > 0) {
+    selected.push_back (0);
+  }
+
+  if (selected.size () > 0) {
+
+    int dirty_layouts = 0;
+    std::string dirty_files;
+
+    for (std::vector <int>::const_iterator i = selected.begin (); i != selected.end (); ++i) {
+
+      const lay::CellView &cv = view ()->cellview (*i);
+
+      if (cv->layout ().is_editable () && cv->is_dirty ()) {
+        ++dirty_layouts;
+        if (dirty_layouts == max_dirty_files) {
+          dirty_files += "\n...";
+        } else if (dirty_layouts < max_dirty_files) {
+          if (! dirty_files.empty ()) {
+            dirty_files += "\n";
+          }
+          dirty_files += cv->name ();
+        }
+      }
+
+    }
+
+    bool can_reload = true;
+    if (dirty_layouts != 0) {
+
+      QMessageBox mbox (view ());
+      mbox.setText (tl::to_qstring (tl::to_string (QObject::tr ("The following layouts need saving:\n\n")) + dirty_files + "\n\nPress 'Reload Without Saving' to reload anyhow and discard changes."));
+      mbox.setWindowTitle (QObject::tr ("Save Needed"));
+      mbox.setIcon (QMessageBox::Warning);
+      QAbstractButton *yes_button = mbox.addButton (QObject::tr ("Reload Without Saving"), QMessageBox::YesRole);
+      mbox.addButton (QMessageBox::Cancel);
+
+      mbox.exec ();
+
+      can_reload = (mbox.clickedButton() == yes_button);
+
+    }
+
+    if (can_reload) {
+
+      //  Actually reload
+      for (std::vector <int>::const_iterator i = selected.begin (); i != selected.end (); ++i) {
+        view ()->reload_layout (*i);
+      }
+
+    }
+
+  }
+}
+
+void
+LayoutViewFunctions::do_transform (const db::DCplxTrans &tr)
+{
+  //  end move operations, cancel edit operations
+  view ()->cancel_edits ();
+  view ()->lay::Editables::transform (tr);
+}
+
+void
+LayoutViewFunctions::transform_layout (const db::DCplxTrans &tr_mic)
+{
+  //  end move operations, cancel edit operations
+  view ()->cancel_edits ();
+  view ()->clear_selection ();
+
+  int cv_index = view ()->active_cellview_index ();
+  if (cv_index >= 0) {
+
+    db::Layout &layout = view ()->cellview (cv_index)->layout ();
+
+    db::ICplxTrans tr (db::DCplxTrans (1.0 / layout.dbu ()) * tr_mic * db::DCplxTrans (layout.dbu ()));
+
+    bool has_proxy = false;
+    for (db::Layout::const_iterator c = layout.begin (); ! has_proxy && c != layout.end (); ++c) {
+      has_proxy = c->is_proxy ();
+    }
+
+    if (has_proxy && 
+        QMessageBox::question (view (),
+                               QObject::tr ("Transforming PCells Or Library Cells"), 
+                               QObject::tr ("The layout contains PCells or library cells or both.\n"
+                                            "Any changes to such cells may be lost when their layout is refreshed later.\n"
+                                            "Consider using 'Convert all cells to static' before transforming the layout.\n"
+                                            "\n"
+                                            "Would you like to continue?\n"
+                                            "Choose 'Yes' to continue anyway. Choose 'No' to cancel."), 
+                               QMessageBox::Yes | QMessageBox::No) != QMessageBox::Yes) {
+      return;
+    }
+
+    view ()->transaction (tl::to_string (QObject::tr ("Transform layout")));
+    layout.transform (tr);
+    view ()->commit ();
+
+  }
+}
+
+void 
+LayoutViewFunctions::cm_lay_flip_x ()
+{
+  transform_layout (db::DCplxTrans (db::FTrans::m90));
+}
+
+void 
+LayoutViewFunctions::cm_lay_flip_y ()
+{
+  transform_layout (db::DCplxTrans (db::FTrans::m0));
+}
+
+void 
+LayoutViewFunctions::cm_lay_rot_ccw ()
+{
+  db::DCplxTrans tr (db::DFTrans::r90);
+  transform_layout (db::DCplxTrans (db::FTrans::r90));
+}
+
+void 
+LayoutViewFunctions::cm_lay_rot_cw ()
+{
+  transform_layout (db::DCplxTrans (db::FTrans::r270));
+}
+
+void 
+LayoutViewFunctions::cm_lay_free_rot ()
+{
+  bool ok = false;
+  QString s = QInputDialog::getText (QApplication::activeWindow (), 
+                                     QObject::tr ("Free rotation"), 
+                                     QObject::tr ("Rotation angle in degree (counterclockwise)"), 
+                                     QLineEdit::Normal, QString::fromUtf8 ("0.0"), 
+                                     &ok);
+
+  if (ok) {
+
+    double angle = 0.0;
+    tl::from_string (tl::to_string (s), angle);
+
+    transform_layout (db::DCplxTrans (1.0, angle, false, db::DVector ()));
+
+  }
+}
+
+void 
+LayoutViewFunctions::cm_lay_scale ()
+{
+  bool ok = false;
+  QString s = QInputDialog::getText (QApplication::activeWindow (), 
+                                     QObject::tr ("Scaling"), 
+                                     QObject::tr ("Scaling factor"), 
+                                     QLineEdit::Normal, QString::fromUtf8 ("1.0"), 
+                                     &ok);
+
+  if (ok) {
+
+    double scale = 0.0;
+    tl::from_string (tl::to_string (s), scale);
+
+    transform_layout (db::DCplxTrans (scale));
+
+  }
+}
+
+void 
+LayoutViewFunctions::cm_lay_move ()
+{
+  lay::MoveOptionsDialog options (view ());
+  if (options.exec_dialog (m_move_dist)) {
+    transform_layout (db::DCplxTrans (m_move_dist));
+  }
+}
+
+void 
+LayoutViewFunctions::cm_sel_flip_x ()
+{
+  db::DCplxTrans tr (db::DFTrans::m90);
+  db::DBox sel_bbox (view ()->lay::Editables::selection_bbox ());
+  if (! sel_bbox.empty ()) {
+    tr = db::DCplxTrans (sel_bbox.center () - db::DPoint ()) * tr * db::DCplxTrans (db::DPoint () - sel_bbox.center ());
+  }
+  do_transform (tr);
+}
+
+void 
+LayoutViewFunctions::cm_sel_flip_y ()
+{
+  db::DCplxTrans tr (db::DFTrans::m0);
+  db::DBox sel_bbox (view ()->lay::Editables::selection_bbox ());
+  if (! sel_bbox.empty ()) {
+    tr = db::DCplxTrans (sel_bbox.center () - db::DPoint ()) * tr * db::DCplxTrans (db::DPoint () - sel_bbox.center ());
+  }
+  do_transform (tr);
+}
+
+void 
+LayoutViewFunctions::cm_sel_rot_ccw ()
+{
+  db::DCplxTrans tr (db::DFTrans::r90);
+  db::DBox sel_bbox (view ()->lay::Editables::selection_bbox ());
+  if (! sel_bbox.empty ()) {
+    tr = db::DCplxTrans (sel_bbox.center () - db::DPoint ()) * tr * db::DCplxTrans (db::DPoint () - sel_bbox.center ());
+  }
+  do_transform (tr);
+}
+
+void 
+LayoutViewFunctions::cm_sel_rot_cw ()
+{
+  db::DCplxTrans tr (db::DFTrans::r270);
+  db::DBox sel_bbox (view ()->lay::Editables::selection_bbox ());
+  if (! sel_bbox.empty ()) {
+    tr = db::DCplxTrans (sel_bbox.center () - db::DPoint ()) * tr * db::DCplxTrans (db::DPoint () - sel_bbox.center ());
+  }
+  do_transform (tr);
+}
+
+void 
+LayoutViewFunctions::cm_sel_free_rot ()
+{
+  bool ok = false;
+  QString s = QInputDialog::getText (QApplication::activeWindow (), 
+                                     QObject::tr ("Free rotation"), 
+                                     QObject::tr ("Rotation angle in degree (counterclockwise)"), 
+                                     QLineEdit::Normal, QString::fromUtf8 ("0.0"), 
+                                     &ok);
+
+  if (ok) {
+
+    double angle = 0.0;
+    tl::from_string (tl::to_string (s), angle);
+
+    db::DCplxTrans tr = db::DCplxTrans (1.0, angle, false, db::DVector ());
+    db::DBox sel_bbox (view ()->lay::Editables::selection_bbox ());
+    if (! sel_bbox.empty ()) {
+      tr = db::DCplxTrans (sel_bbox.center () - db::DPoint ()) * tr * db::DCplxTrans (db::DPoint () - sel_bbox.center ());
+    }
+    do_transform (tr);
+
+  }
+}
+
+void 
+LayoutViewFunctions::cm_sel_scale ()
+{
+  bool ok = false;
+  QString s = QInputDialog::getText (QApplication::activeWindow (), 
+                                     QObject::tr ("Scaling"), 
+                                     QObject::tr ("Scaling factor"), 
+                                     QLineEdit::Normal, QString::fromUtf8 ("1.0"), 
+                                     &ok);
+
+  if (ok) {
+
+    double scale = 0.0;
+    tl::from_string (tl::to_string (s), scale);
+
+    db::DCplxTrans tr = db::DCplxTrans (scale);
+    db::DBox sel_bbox (view ()->lay::Editables::selection_bbox ());
+    if (! sel_bbox.empty ()) {
+      tr = db::DCplxTrans (sel_bbox.center () - db::DPoint ()) * tr * db::DCplxTrans (db::DPoint () - sel_bbox.center ());
+    }
+    do_transform (tr);
+
+  }
+}
+
+void
+LayoutViewFunctions::cm_sel_move_interactive ()
+{
+  if (view ()->move_service ()->begin_move ()) {
+    view ()->switch_mode (-1);  //  move mode
+  }
+}
+
+void 
+LayoutViewFunctions::cm_sel_move_to ()
+{
+  db::DBox sel_bbox (view ()->lay::Editables::selection_bbox ());
+  if (sel_bbox.empty ()) {
+    throw tl::Exception (tl::to_string (QObject::tr ("Nothing selected to move")));
+  }
+
+  double x = sel_bbox.left () + (sel_bbox.width () * (1 + m_move_to_origin_mode_x) * 0.5);
+  double y = sel_bbox.bottom () + (sel_bbox.height () * (1 + m_move_to_origin_mode_y) * 0.5);
+  db::DPoint move_target (x, y);
+
+  lay::MoveToOptionsDialog options (view ());
+  if (options.exec_dialog (m_move_to_origin_mode_x, m_move_to_origin_mode_y, move_target)) {
+
+    x = sel_bbox.left () + (sel_bbox.width () * (1 + m_move_to_origin_mode_x) * 0.5);
+    y = sel_bbox.bottom () + (sel_bbox.height () * (1 + m_move_to_origin_mode_y) * 0.5);
+
+    do_transform (db::DCplxTrans (move_target - db::DPoint (x, y)));
+
+  }
+}
+
+void 
+LayoutViewFunctions::cm_sel_move ()
+{
+  lay::MoveOptionsDialog options (view ());
+  if (options.exec_dialog (m_move_dist)) {
+    do_transform (db::DCplxTrans (m_move_dist));
+  }
+}
+
+void
+LayoutViewFunctions::cm_copy_layer ()
+{
+  struct { int *cv; int *layer; } specs [] = {
+    { &m_copy_cva, &m_copy_layera },
+    { &m_copy_cvr, &m_copy_layerr }
+  };
+
+  for (unsigned int i = 0; i < sizeof (specs) / sizeof (specs[0]); ++i) {
+
+    int &cv = *(specs[i].cv);
+    int &layer = *(specs[i].layer);
+
+    if (cv >= int (view ()->cellviews ())) {
+      cv = -1;
+    }
+
+    int index = view ()->active_cellview_index ();
+    if (cv < 0) {
+      cv = index;
+    }
+
+    if (cv < 0 || ! view ()->cellview (cv)->layout ().is_valid_layer ((unsigned int) layer)) {
+      layer = -1;
+    }
+
+  }
+
+  lay::DuplicateLayerDialog dialog (view ());
+  if (dialog.exec_dialog (view (), m_copy_cva, m_copy_layera, m_copy_cvr, m_copy_layerr, m_duplicate_hier_mode, m_clear_before)) {
+
+    bool supports_undo = true;
+
+    if (manager () && manager ()->is_enabled ()) {
+
+      lay::TipDialog td (QApplication::activeWindow (), 
+                         tl::to_string (QObject::tr ("Undo buffering for the following operation can be memory and time consuming.\nChoose \"Yes\" to use undo buffering or \"No\" for no undo buffering. Warning: in the latter case, the undo history will be lost.\n\nChoose undo buffering?")), 
+                         "copy-layer-undo-buffering",
+                         lay::TipDialog::yesnocancel_buttons);
+
+      lay::TipDialog::button_type button = lay::TipDialog::null_button;
+      td.exec_dialog (button);
+      if (button == lay::TipDialog::cancel_button) {
+        return;
+      }
+
+      supports_undo = (button == lay::TipDialog::yes_button);
+
+    } else {
+      supports_undo = false;
+    }
+
+    view ()->cancel ();
+
+    if (manager ()) {
+      if (! supports_undo) {
+        manager ()->clear ();
+      } else {
+        manager ()->transaction (tl::to_string (QObject::tr ("Duplicate layer"))); 
+      }
+    }
+
+    try {
+
+      bool same_layout = (&view ()->cellview (m_copy_cvr)->layout () == &view ()->cellview (m_copy_cva)->layout ());
+      if (same_layout && m_copy_layera == m_copy_layerr) {
+        throw tl::Exception (tl::to_string (QObject::tr ("Source and target layer must not be identical for duplicate operation")));
+      }
+
+      if (m_duplicate_hier_mode == 0) {
+
+        //  clear the result layer for all called cells in flat mode
+        if (m_clear_before) {
+          std::set<db::cell_index_type> called_cells;
+          called_cells.insert (view ()->cellview (m_copy_cvr).cell_index ());
+          view ()->cellview (m_copy_cvr).cell ()->collect_called_cells (called_cells);
+          for (std::set<db::cell_index_type>::const_iterator c = called_cells.begin (); c != called_cells.end (); ++c) {
+            view ()->cellview (m_copy_cvr)->layout ().cell (*c).shapes (m_copy_layerr).clear ();
+          }
+        }
+
+        db::Cell &target_cell = *view ()->cellview (m_copy_cvr).cell ();
+
+        if (! same_layout) {
+
+          //  flat mode (different layouts)
+          db::PropertyMapper pm (view ()->cellview (m_copy_cvr)->layout (), view ()->cellview (m_copy_cva)->layout ());
+          for (db::RecursiveShapeIterator si (view ()->cellview (m_copy_cva)->layout (), *view ()->cellview (m_copy_cva).cell (), m_copy_layera); ! si.at_end (); ++si) {
+            target_cell.shapes (m_copy_layerr).insert (*si, si.trans (), pm);
+          }
+
+        } else {
+
+          //  flat mode (same layouts)
+          tl::ident_map<db::Layout::properties_id_type> pm1;
+          db::Shapes &res = target_cell.shapes (m_copy_layerr);
+          
+          db::Layout &layout = view ()->cellview (m_copy_cvr)->layout ();
+          try {
+
+            //  using update/start_layout and end_changes improves the performance since changing the 
+            //  shapes collection will invalidate the layout and cause updates inside the RecursiveShapeIerator
+            layout.update ();
+            layout.start_changes ();
+            for (db::RecursiveShapeIterator si (view ()->cellview (m_copy_cva)->layout (), *view ()->cellview (m_copy_cva).cell (), m_copy_layera); ! si.at_end (); ++si) {
+              res.insert (*si, si.trans (), pm1);
+            }
+            layout.end_changes ();
+
+          } catch (...) {
+            layout.end_changes ();
+            throw;
+          }
+
+        }
+        
+      } else if (m_duplicate_hier_mode == 1) {
+
+        db::Cell &cell = *view ()->cellview (m_copy_cva).cell ();
+        db::Cell &target_cell = *view ()->cellview (m_copy_cvr).cell ();
+
+        if (m_clear_before) {
+          target_cell.clear (m_copy_layerr);
+        } 
+
+        if (m_copy_cvr == m_copy_cva) {
+
+          //  current cell only mode: identical cell
+          cell.copy (m_copy_layera, m_copy_layerr);
+
+        } else if (! same_layout) {
+
+          //  current cell only mode (different layouts)
+          db::PropertyMapper pm (view ()->cellview (m_copy_cvr)->layout (), view ()->cellview (m_copy_cva)->layout ());
+          for (db::Shapes::shape_iterator si = view ()->cellview (m_copy_cva).cell ()->shapes (m_copy_layera).begin (db::ShapeIterator::All); ! si.at_end (); ++si) {
+            target_cell.shapes (m_copy_layerr).insert (*si, pm);
+          }
+
+        } else {
+
+          //  current cell only mode (same layouts, but different cells)
+          for (db::Shapes::shape_iterator si = view ()->cellview (m_copy_cva).cell ()->shapes (m_copy_layera).begin (db::ShapeIterator::All); ! si.at_end (); ++si) {
+            target_cell.shapes (m_copy_layerr).insert (*si);
+          }
+
+        }
+        
+      } else if (m_duplicate_hier_mode == 2) {
+
+        //  subcells cell by cell - source and target layout must be identical
+        std::set<db::cell_index_type> called_cells;
+        view ()->cellview (m_copy_cva).cell ()->collect_called_cells (called_cells);
+        called_cells.insert (view ()->cellview (m_copy_cva).cell_index ());
+
+        db::Layout &layout = view ()->cellview (m_copy_cva)->layout ();
+        for (std::set<db::cell_index_type>::const_iterator c = called_cells.begin (); c != called_cells.end (); ++c) {
+          db::Cell &cell = layout.cell (*c);
+          if (m_clear_before) {
+            cell.clear (m_copy_layerr);
+          } 
+          cell.copy (m_copy_layera, m_copy_layerr);
+        }
+
+      }
+
+      if (manager () && supports_undo) {
+        manager ()->commit ();
+      }
+
+    } catch (...) {
+      if (manager () && supports_undo) {
+        manager ()->commit ();
+      }
+      throw;
+    }
+
+  }
+}
+
+void
+LayoutViewFunctions::cm_new_layer ()
+{
+  int index = view ()->active_cellview_index ();
+
+  if (index >= 0 && int (view ()->cellviews ()) > index) {
+
+    const lay::CellView &cv = view ()->cellview (index);
+
+    lay::NewLayerPropertiesDialog prop_dia (view ());
+    if (prop_dia.exec_dialog (cv, m_new_layer_props)) {
+
+      for (unsigned int l = 0; l < cv->layout ().layers (); ++l) {
+        if (cv->layout ().is_valid_layer (l) && cv->layout ().get_properties (l).log_equal (m_new_layer_props)) {
+          throw tl::Exception (tl::to_string (QObject::tr ("A layer with that signature already exists: ")) + m_new_layer_props.to_string ());
+        }
+      }
+
+      view ()->transaction (tl::to_string (QObject::tr ("New layer")));
+
+      unsigned int l = cv->layout ().insert_layer (m_new_layer_props);
+      std::vector <unsigned int> nl;
+      nl.push_back (l);
+      view ()->add_new_layers (nl, index);
+      view ()->update_content ();
+
+      view ()->commit ();
+
+    }
+
+  }
+}
+
+void
+LayoutViewFunctions::cm_align_cell_origin ()
+{
+  int cv_index = view ()->active_cellview_index ();
+  if (cv_index >= 0) {
+
+    const db::Cell *cell = view ()->cellview (cv_index).cell ();
+    if (! cell) {
+      return;
+    }
+    if (cell->is_proxy ()) {
+      throw tl::Exception (tl::to_string (QObject::tr ("Cannot use this function on a PCell or library cell")));
+    }
+
+    lay::AlignCellOptionsDialog dialog (view ());
+    if (dialog.exec_dialog (m_align_cell_options)) {
+
+      view ()->clear_selection ();
+
+      view ()->transaction (tl::to_string (QObject::tr ("Align cell origin")));
+
+      db::Box bbox;
+
+      if (m_align_cell_options.visible_only) {
+        for (lay::LayerPropertiesConstIterator l = view ()->begin_layers (); !l.at_end (); ++l) {
+          if (! l->has_children () && l->layer_index () >= 0 && l->cellview_index () == cv_index && l->visible (true /*real*/)) {
+            bbox += cell->bbox (l->layer_index ());
+          }
+        }
+      } else {
+        bbox = cell->bbox ();
+      }
+
+      db::Coord refx, refy;
+      switch (m_align_cell_options.mode_x) {
+      case -1:
+        refx = bbox.left ();
+        break;
+      case 1:
+        refx = bbox.right ();
+        break;
+      default:
+        refx = bbox.center ().x ();
+        break;
+      }
+      switch (m_align_cell_options.mode_y) {
+      case -1:
+        refy = bbox.bottom ();
+        break;
+      case 1:
+        refy = bbox.top ();
+        break;
+      default:
+        refy = bbox.center ().y ();
+        break;
+      }
+
+      db::Layout &layout = view ()->cellview (cv_index)->layout ();
+      db::Cell &nc_cell = layout.cell (cell->cell_index ());
+
+      db::Trans t (db::Vector (-refx + db::coord_traits<db::Coord>::rounded (m_align_cell_options.xpos / layout.dbu ()), -refy + db::coord_traits<db::Coord>::rounded (m_align_cell_options.ypos / layout.dbu ())));
+
+      for (unsigned int i = 0; i < layout.layers (); ++i) {
+        if (layout.is_valid_layer (i)) {
+          db::Shapes &shapes = nc_cell.shapes (i);
+          for (db::Shapes::shape_iterator s = shapes.begin (db::ShapeIterator::All); ! s.at_end (); ++s) {
+            shapes.transform (*s, t);
+          }
+        }
+      }
+
+      for (db::Cell::const_iterator inst = nc_cell.begin (); ! inst.at_end (); ++inst) {
+        nc_cell.transform (*inst, t);
+      }
+
+      if (m_align_cell_options.adjust_parents) {
+
+        std::vector<std::pair<db::Cell *, db::Instance> > insts_to_modify;
+        for (db::Cell::parent_inst_iterator pi = nc_cell.begin_parent_insts (); ! pi.at_end (); ++pi) {
+          insts_to_modify.push_back (std::make_pair (& layout.cell (pi->parent_cell_index ()), pi->child_inst ()));
+        }
+
+        db::Trans ti (db::Vector (refx, refy));
+        for (std::vector<std::pair<db::Cell *, db::Instance> >::const_iterator im = insts_to_modify.begin (); im != insts_to_modify.end (); ++im) {
+          im->first->transform (im->second, db::Trans (db::Vector (im->second.complex_trans ().trans (db::Vector (refx, refy)))));
+        }
+
+      }
+
+      view ()->commit ();
+
+    }
+
+  }
+}
+
+void
+LayoutViewFunctions::cm_edit_layer ()
+{
+  lay::LayerPropertiesConstIterator sel = view ()->current_layer ();
+  if (sel.is_null ()) {
+    throw tl::Exception (tl::to_string (QObject::tr ("No layer selected for editing it's properties")));
+  }
+
+  int index = sel->cellview_index ();
+  if (sel->has_children () || index < 0 || int (view ()->cellviews ()) <= index || sel->layer_index () < 0) {
+    throw tl::Exception (tl::to_string (QObject::tr ("No valid layer selected for editing it's properties")));
+  }
+
+  const lay::CellView &cv = view ()->cellview (index);
+
+  db::LayerProperties layer_props = cv->layout ().get_properties ((unsigned int) sel->layer_index ());
+
+  lay::NewLayerPropertiesDialog prop_dia (view ());
+  if (prop_dia.exec_dialog (cv, layer_props)) {
+
+    for (unsigned int l = 0; l < cv->layout ().layers (); ++l) {
+      if (cv->layout ().is_valid_layer (l) && int (l) != sel->layer_index () && cv->layout ().get_properties (l).log_equal (layer_props)) {
+        throw tl::Exception (tl::to_string (QObject::tr ("A layer with that signature already exists: ")) + layer_props.to_string ());
+      }
+    }
+
+    view ()->transaction (tl::to_string (QObject::tr ("Edit layer")));
+
+    cv->layout ().set_properties (sel->layer_index (), layer_props);
+
+    lay::LayerProperties lp (*sel);
+    lay::ParsedLayerSource s = lp.source (false);
+    s.layer (layer_props.layer);
+    s.datatype (layer_props.datatype);
+    if (! layer_props.name.empty ()) {
+      s.name (layer_props.name);
+    } else {
+      s.clear_name ();
+    }
+    lp.set_source (s);
+    view ()->set_properties (sel, lp);
+
+    view ()->update_content ();
+
+    view ()->commit ();
+
+  }
+}
+
+void
+LayoutViewFunctions::cm_delete_layer ()
+{
+  std::vector<lay::LayerPropertiesConstIterator> sel = view ()->selected_layers ();
+  std::sort (sel.begin (), sel.end (), CompareLayerIteratorBottomUp ());
+
+  //  collect valid layers
+  std::vector<lay::LayerPropertiesConstIterator> valid_sel;
+  std::set<std::pair<db::Layout *, unsigned int> > valid_layers;
+  for (std::vector<lay::LayerPropertiesConstIterator>::const_iterator si = sel.begin (); si != sel.end (); ++si) {
+    int cv_index = (*si)->cellview_index ();
+    const lay::CellView &cv = view ()->cellview (cv_index);
+    if (!(*si)->has_children () && cv_index >= 0 && int (view ()->cellviews ()) > cv_index && (*si)->layer_index () >= 0 && cv.is_valid ()) {
+      valid_sel.push_back (*si);
+      valid_layers.insert (std::make_pair (&cv->layout (), (*si)->layer_index ()));
+    }
+  }
+
+  if (valid_sel.empty ()) {
+    throw tl::Exception (tl::to_string (QObject::tr ("No or no valid layer selected for deleting them")));
+  }
+
+  view ()->cancel_edits ();
+  view ()->clear_selection ();
+
+  view ()->transaction (tl::to_string (QObject::tr ("Delete layers")));
+
+  //  Hint: delete_layer must come before the layers are actually deleted in because
+  //  for undo this must be the last thing to do (otherwise the layout is not propertly set up)
+
+  for (std::vector<lay::LayerPropertiesConstIterator>::const_iterator si = valid_sel.begin (); si != valid_sel.end (); ++si) {
+    lay::LayerPropertiesConstIterator lp = *si;
+    view ()->delete_layer (lp);
+  }
+
+  for (std::set<std::pair<db::Layout *, unsigned int> >::const_iterator li = valid_layers.begin (); li != valid_layers.end(); ++li) {
+
+    unsigned int layer_index = li->second;
+    db::Layout *layout = li->first;
+
+    for (db::Layout::iterator c = layout->begin (); c != layout->end (); ++c) {
+      c->shapes (layer_index).clear ();
+    }
+
+    layout->delete_layer (layer_index);
+
+  }
+
+  view ()->update_content ();
+
+  view ()->commit ();
+}
+
+void
+LayoutViewFunctions::cm_clear_layer ()
+{
+  std::vector<lay::LayerPropertiesConstIterator> sel = view ()->selected_layers ();
+  if (sel.empty ()) {
+    throw tl::Exception (tl::to_string (QObject::tr ("No layer selected for clearing")));
+  }
+
+  lay::ClearLayerModeDialog mode_dialog (view ());
+  if (mode_dialog.exec_dialog (m_layer_hier_mode)) {
+
+    view ()->cancel_edits ();
+    view ()->clear_selection ();
+
+    view ()->transaction (tl::to_string (QObject::tr ("Clear layer")));
+
+    for (std::vector<lay::LayerPropertiesConstIterator>::const_iterator si = sel.begin (); si != sel.end (); ++si) {
+
+      if (! (*si)->has_children () && (*si)->layer_index () >= 0 && view ()->cellview ((*si)->cellview_index ()).is_valid ()) {
+
+        int layer_index = (*si)->layer_index ();
+        const lay::CellView &cv = view ()->cellview ((*si)->cellview_index ());
+
+        if (m_layer_hier_mode == 0) {
+          cv.cell ()->clear ((unsigned int) layer_index);
+        } else if (m_layer_hier_mode == 1) {
+
+          cv.cell ()->clear ((unsigned int) layer_index);
+
+          std::set <db::cell_index_type> called_cells;
+          cv.cell ()->collect_called_cells (called_cells);
+          for (std::set <db::cell_index_type>::const_iterator cc = called_cells.begin (); cc != called_cells.end (); ++cc) {
+            cv->layout ().cell (*cc).clear ((unsigned int) layer_index);
+          }
+
+        } else {
+          cv->layout ().clear_layer ((unsigned int) layer_index);
+        }
+
+      }
+
+    }
+
+    view ()->commit ();
+
+  }
+}
+
+// ------------------------------------------------------------
+//  Declaration of the "plugin" for the menu entries
+
+class LayoutViewPluginDeclaration
+  : public lay::PluginDeclaration
+{
+public:
+  virtual void get_menu_entries (std::vector<lay::MenuEntry> &menu_entries) const
+  {
+    std::string at;
+
+    //  secret menu entries
+    at = "@secrets.end";
+    menu_entries.push_back (lay::menu_item ("cm_paste_interactive", "paste_interactive:edit", at, tl::to_string (QObject::tr ("Paste Interactive"))));
+    menu_entries.push_back (lay::menu_item ("cm_duplicate_interactive", "duplicate_interactive:edit", at, tl::to_string (QObject::tr ("Duplicate Interactive"))));
+    menu_entries.push_back (lay::menu_item ("cm_sel_move_interactive", "sel_move_interactive:edit", at, tl::to_string (QObject::tr ("Move Interactive"))));
+    menu_entries.push_back (lay::menu_item ("cm_select_next_item", "select_next_item:edit", at, tl::to_string (QObject::tr ("Select Next Item(Space)"))));
+    menu_entries.push_back (lay::menu_item ("cm_select_next_item_add", "select_next_item_add:edit", at, tl::to_string (QObject::tr ("Select Next Item too(Shift+Space)"))));
+
+    at = "edit_menu.edit_options_group";
+    menu_entries.push_back (lay::menu_item ("cm_undo", "undo:edit", at, tl::to_string (QObject::tr ("Undo(Ctrl+Z)"))));
+    menu_entries.push_back (lay::menu_item ("cm_redo", "redo:edit", at, tl::to_string (QObject::tr ("Redo(Ctrl+Y)"))));
+
+    menu_entries.push_back (lay::separator ("basic_group", at));
+    menu_entries.push_back (lay::submenu ("layout_menu:edit:edit_mode", at, tl::to_string (QObject::tr ("Layout"))));
+    {
+      std::string at = "edit_menu.layout_menu.end";
+      menu_entries.push_back (lay::menu_item ("cm_lay_flip_x", "lay_flip_x:edit_mode", at, tl::to_string (QObject::tr ("Flip Horizontally"))));
+      menu_entries.push_back (lay::menu_item ("cm_lay_flip_y", "lay_flip_y:edit_mode", at, tl::to_string (QObject::tr ("Flip Vertically"))));
+      menu_entries.push_back (lay::menu_item ("cm_lay_rot_cw", "lay_rot_cw:edit_mode", at, tl::to_string (QObject::tr ("Rotate Clockwise"))));
+      menu_entries.push_back (lay::menu_item ("cm_lay_rot_ccw", "lay_rot_ccw:edit_mode", at, tl::to_string (QObject::tr ("Rotate Counterclockwise"))));
+      menu_entries.push_back (lay::menu_item ("cm_lay_free_rot", "lay_free_rot:edit_mode", at, tl::to_string (QObject::tr ("Rotation By Angle"))));
+      menu_entries.push_back (lay::menu_item ("cm_lay_scale", "lay_scale:edit_mode", at, tl::to_string (QObject::tr ("Scale"))));
+      menu_entries.push_back (lay::menu_item ("cm_lay_move", "lay_move:edit_mode", at, tl::to_string (QObject::tr ("Move By"))));
+      menu_entries.push_back (lay::separator ("cellop_group", at));
+      menu_entries.push_back (lay::menu_item ("cm_lay_convert_to_static", "lay_convert_to_static:edit_mode", at, tl::to_string (QObject::tr ("Convert All Cells To Static"))));
+    }
+
+    menu_entries.push_back (lay::submenu ("cell_menu:edit:edit_mode", at, tl::to_string (QObject::tr ("Cell"))));
+    {
+      std::string at = "edit_menu.cell_menu.end";
+      menu_entries.push_back (lay::menu_item ("cm_new_cell", "new_cell:edit:edit_mode", at, tl::to_string (QObject::tr ("New Cell"))));
+      menu_entries.push_back (lay::menu_item ("cm_cell_delete", "delete_cell:edit:edit_mode", at, tl::to_string (QObject::tr ("Delete Cell"))));
+      menu_entries.push_back (lay::menu_item ("cm_cell_rename", "rename_cell:edit:edit_mode", at, tl::to_string (QObject::tr ("Rename Cell"))));
+      menu_entries.push_back (lay::menu_item ("cm_cell_replace", "replace_cell:edit:edit_mode", at, tl::to_string (QObject::tr ("Replace Cell"))));
+      menu_entries.push_back (lay::menu_item ("cm_cell_flatten", "flatten_cell:edit:edit_mode", at, tl::to_string (QObject::tr ("Flatten Cell"))));
+      menu_entries.push_back (lay::separator ("ops_group", at));
+      menu_entries.push_back (lay::menu_item ("cm_adjust_origin", "adjust_cell_origin:edit:edit_mode", at, tl::to_string (QObject::tr ("Adjust Origin"))));
+      menu_entries.push_back (lay::menu_item ("cm_cell_convert_to_static", "convert_cell_to_static:edit_mode", at, tl::to_string (QObject::tr ("Convert Cell To Static"))));
+      menu_entries.push_back (lay::separator ("props_group", at));
+      menu_entries.push_back (lay::menu_item ("cm_cell_user_properties", "user_properties", at, tl::to_string (QObject::tr ("User Properties"))));
+    }
+
+    menu_entries.push_back (lay::submenu ("layer_menu:edit:edit_mode", at, tl::to_string (QObject::tr ("Layer"))));
+    {
+      std::string at = "edit_menu.layer_menu.end";
+      menu_entries.push_back (lay::menu_item ("cm_new_layer", "new_layer:edit:edit_mode", at, tl::to_string (QObject::tr ("New Layer"))));
+      menu_entries.push_back (lay::menu_item ("cm_clear_layer", "clear_layer:edit:edit_mode", at, tl::to_string (QObject::tr ("Clear Layer"))));
+      menu_entries.push_back (lay::menu_item ("cm_delete_layer", "delete_layer:edit:edit_mode", at, tl::to_string (QObject::tr ("Delete Layer"))));
+      menu_entries.push_back (lay::menu_item ("cm_copy_layer", "copy_layer:edit:edit_mode", at, tl::to_string (QObject::tr ("Copy Layer"))));
+      menu_entries.push_back (lay::menu_item ("cm_edit_layer", "edit_layer:edit:edit_mode", at, tl::to_string (QObject::tr ("Edit Layer Specification"))));
+    }
+
+    menu_entries.push_back (lay::submenu ("selection_menu:edit", at, tl::to_string (QObject::tr ("Selection"))));
+    {
+      std::string at = "edit_menu.selection_menu.end";
+      menu_entries.push_back (lay::menu_item ("cm_sel_flip_x", "sel_flip_x", at, tl::to_string (QObject::tr ("Flip Horizontally"))));
+      menu_entries.push_back (lay::menu_item ("cm_sel_flip_y", "sel_flip_y", at, tl::to_string (QObject::tr ("Flip Vertically"))));
+      menu_entries.push_back (lay::menu_item ("cm_sel_rot_cw", "sel_rot_cw", at, tl::to_string (QObject::tr ("Rotate Clockwise"))));
+      menu_entries.push_back (lay::menu_item ("cm_sel_rot_ccw", "sel_rot_ccw", at, tl::to_string (QObject::tr ("Rotate Counterclockwise"))));
+      menu_entries.push_back (lay::menu_item ("cm_sel_free_rot", "sel_free_rot", at, tl::to_string (QObject::tr ("Rotation By Angle"))));
+      menu_entries.push_back (lay::menu_item ("cm_sel_scale", "sel_scale", at, tl::to_string (QObject::tr ("Scale"))));
+      menu_entries.push_back (lay::menu_item ("cm_sel_move", "sel_move", at, tl::to_string (QObject::tr ("Move By"))));
+      menu_entries.push_back (lay::menu_item ("cm_sel_move_to", "sel_move_to", at, tl::to_string (QObject::tr ("Move To"))));
+    }
+
+    menu_entries.push_back (lay::separator ("utils_group", at));
+    menu_entries.push_back (lay::submenu ("utils_menu:edit:edit_mode", at, tl::to_string (QObject::tr ("Utilities"))));
+
+    menu_entries.push_back (lay::separator ("misc_group", at));
+    menu_entries.push_back (lay::menu_item ("cm_delete", "delete:edit", at, tl::to_string (QObject::tr ("Delete(Del)"))));
+    menu_entries.push_back (lay::menu_item ("cm_show_properties", "show_properties:edit", at, tl::to_string (QObject::tr ("Properties(Q)"))));
+
+    menu_entries.push_back (lay::separator ("cpc_group", at));
+    menu_entries.push_back (lay::menu_item ("cm_copy", "copy:edit", at, tl::to_string (QObject::tr ("Copy(Ctrl+C)"))));
+    menu_entries.push_back (lay::menu_item ("cm_cut", "cut:edit", at, tl::to_string (QObject::tr ("Cut(Ctrl+X)"))));
+    menu_entries.push_back (lay::menu_item ("cm_paste", "paste:edit", at, tl::to_string (QObject::tr ("Paste(Ctrl+V)"))));
+    menu_entries.push_back (lay::menu_item ("cm_duplicate", "duplicate:edit", at, tl::to_string (QObject::tr ("Duplicate(Ctrl+B)"))));
+
+    menu_entries.push_back (lay::separator ("modes_group", at));
+    menu_entries.push_back (lay::submenu ("mode_menu", at, tl::to_string (QObject::tr ("Mode"))));
+
+    menu_entries.push_back (lay::submenu ("select_menu", at, tl::to_string (QObject::tr ("Select"))));
+    {
+      std::string at = "edit_menu.select_menu.end";
+      menu_entries.push_back (lay::menu_item ("cm_select_all", "select_all", at, tl::to_string (QObject::tr ("Select All"))));
+      menu_entries.push_back (lay::menu_item ("cm_unselect_all", "unselect_all", at, tl::to_string (QObject::tr ("Unselect All"))));
+      menu_entries.push_back (lay::separator ("edit_select_basic_group", at));
+      menu_entries.push_back (lay::menu_item ("lv:enable_all", "enable_all", at, tl::to_string (QObject::tr ("Enable All"))));
+      menu_entries.push_back (lay::menu_item ("lv:disable_all", "disable_all", at, tl::to_string (QObject::tr ("Disable All"))));
+      menu_entries.push_back (lay::separator ("edit_select_individual_group", at));
+    };
+
+    menu_entries.push_back (lay::separator ("cancel_group", at));
+    menu_entries.push_back (lay::menu_item ("cm_cancel", "cancel", at, tl::to_string (QObject::tr ("Cancel(Esc)"))));
+
+    at = "bookmark_menu.end";
+    menu_entries.push_back (lay::submenu ("goto_bookmark_menu", at, tl::to_string (QObject::tr ("Goto Bookmark"))));
+    menu_entries.push_back (lay::menu_item ("cm_bookmark_view", "bookmark_view", at, tl::to_string (QObject::tr ("Bookmark This View"))));
+
+    menu_entries.push_back (lay::separator ("bookmark_mgm_group", at));
+    menu_entries.push_back (lay::menu_item ("cm_manage_bookmarks", "manage_bookmarks", at, tl::to_string (QObject::tr ("Manage Bookmarks"))));
+    menu_entries.push_back (lay::menu_item ("cm_load_bookmarks", "load_bookmarks", at, tl::to_string (QObject::tr ("Load Bookmarks"))));
+    menu_entries.push_back (lay::menu_item ("cm_save_bookmarks", "save_bookmarks", at, tl::to_string (QObject::tr ("Save Bookmarks"))));
+    menu_entries.push_back (lay::submenu ("open_recent_menu_bookmarks", at, tl::to_string (QObject::tr ("Recent Bookmark Files"))));
+
+    at = "zoom_menu.end";
+    menu_entries.push_back (lay::submenu ("global_trans", at, tl::to_string (QObject::tr ("Global Transformation"))));
+    {
+      std::string at = "zoom_menu.global_trans.end";
+      menu_entries.push_back (lay::config_menu_item ("r0", at, tl::to_string (QObject::tr ("\\(r0\\)<:/r0.png>")), cfg_global_trans, "?r0 *1 0,0"));
+      menu_entries.push_back (lay::config_menu_item ("r90", at, tl::to_string (QObject::tr ("\\(r90\\)<:/r90.png>")), cfg_global_trans, "?r90 *1 0,0"));
+      menu_entries.push_back (lay::config_menu_item ("r180", at, tl::to_string (QObject::tr ("\\(r180\\)<:/r180.png>")), cfg_global_trans, "?r180 *1 0,0"));
+      menu_entries.push_back (lay::config_menu_item ("r270", at, tl::to_string (QObject::tr ("\\(r270\\)<:/r270.png>")), cfg_global_trans, "?r270 *1 0,0"));
+      menu_entries.push_back (lay::config_menu_item ("m0", at, tl::to_string (QObject::tr ("\\(m0\\)<:/m0.png>")), cfg_global_trans, "?m0 *1 0,0"));
+      menu_entries.push_back (lay::config_menu_item ("m45", at, tl::to_string (QObject::tr ("\\(m45\\)<:/m45.png>")), cfg_global_trans, "?m45 *1 0,0"));
+      menu_entries.push_back (lay::config_menu_item ("m90", at, tl::to_string (QObject::tr ("\\(m90\\)<:/m90.png>")), cfg_global_trans, "?m90 *1 0,0"));
+      menu_entries.push_back (lay::config_menu_item ("m135", at, tl::to_string (QObject::tr ("\\(m135\\)<:/m135.png>")), cfg_global_trans, "?m135 *1 0,0"));
+    }
+
+    menu_entries.push_back (lay::separator ("hier_group", at));
+    menu_entries.push_back (lay::menu_item ("cm_max_hier", "max_hier", at, tl::to_string (QObject::tr ("Full Hierarchy(*)"))));
+    menu_entries.push_back (lay::menu_item ("cm_max_hier_0", "max_hier_0", at, tl::to_string (QObject::tr ("Box Only(0)"))));
+    menu_entries.push_back (lay::menu_item ("cm_max_hier_1", "max_hier_1", at, tl::to_string (QObject::tr ("Top Level Only(1)"))));
+    menu_entries.push_back (lay::menu_item ("cm_inc_max_hier", "inc_max_hier", at, tl::to_string (QObject::tr ("Increment Hierarchy(+)"))));
+    menu_entries.push_back (lay::menu_item ("cm_dec_max_hier", "dec_max_hier", at, tl::to_string (QObject::tr ("Decrement Hierarchy(-)"))));
+
+    menu_entries.push_back (lay::separator ("zoom_group", at));
+    menu_entries.push_back (lay::menu_item ("cm_zoom_fit", "zoom_fit", at, tl::to_string (QObject::tr ("Zoom Fit(F2)"))));
+    menu_entries.push_back (lay::menu_item ("cm_zoom_fit_sel", "zoom_fit_sel", at, tl::to_string (QObject::tr ("Zoom Fit Selection(Shift+F2)"))));
+    menu_entries.push_back (lay::menu_item ("cm_zoom_in", "zoom_in", at, tl::to_string (QObject::tr ("Zoom In(Ctrl++)"))));
+    menu_entries.push_back (lay::menu_item ("cm_zoom_out", "zoom_out", at, tl::to_string (QObject::tr ("Zoom Out(Ctrl+-)"))));
+    /* disabled because that interferes with the use of the arrow keys for moving the selection
+    MenuLayoutEntry::separator ("pan_group");
+    menu_entries.push_back (lay::menu_item ("cm_pan_up", "pan_up", at, tl::to_string (QObject::tr ("Pan Up(Up)"))));
+    menu_entries.push_back (lay::menu_item ("cm_pan_down", "pan_down", at, tl::to_string (QObject::tr ("Pan Down(Down)"))));
+    menu_entries.push_back (lay::menu_item ("cm_pan_left", "pan_left", at, tl::to_string (QObject::tr ("Pan Left(Left)"))));
+    menu_entries.push_back (lay::menu_item ("cm_pan_right", "pan_right", at, tl::to_string (QObject::tr ("Pan Right(Right)"))));
+    */
+
+    menu_entries.push_back (lay::separator ("redraw_group", at));
+    menu_entries.push_back (lay::menu_item ("cm_redraw", "redraw", at, tl::to_string (QObject::tr ("Redraw"))));
+    menu_entries.push_back (lay::separator ("state_group", at));
+    menu_entries.push_back (lay::menu_item_copy ("cm_prev_display_state", "prev_display_state", at, "@toolbar.prev_display_state"));
+    menu_entries.push_back (lay::menu_item_copy ("cm_next_display_state", "next_display_state", at, "@toolbar.next_display_state"));
+
+    menu_entries.push_back (lay::separator ("select_group", at));
+    menu_entries.push_back (lay::menu_item ("cm_select_cell", "select_cell:edit", at, tl::to_string (QObject::tr ("Select Cell"))));
+    menu_entries.push_back (lay::menu_item ("cm_select_current_cell", "select_current_cell", at, tl::to_string (QObject::tr ("Show As New Top(Ctrl+S)"))));
+    menu_entries.push_back (lay::menu_item ("cm_goto_position", "goto_position", at, tl::to_string (QObject::tr ("Goto Position(Ctrl+G)"))));
+
+    //  Add a hook for inserting new items after the modes
+    menu_entries.push_back (lay::separator ("end_modes", "@toolbar.end"));
+
+  }
+
+  bool menu_activated (const std::string &symbol) const
+  {
+    if (symbol == "lv:enable_all") {
+
+      for (tl::Registrar<lay::PluginDeclaration>::iterator cls = tl::Registrar<lay::PluginDeclaration>::begin (); cls != tl::Registrar<lay::PluginDeclaration>::end (); ++cls) {
+        cls->set_editable_enabled (true);
+      }
+      return true;
+
+    } else if (symbol == "lv:disable_all") {
+
+      for (tl::Registrar<lay::PluginDeclaration>::iterator cls = tl::Registrar<lay::PluginDeclaration>::begin (); cls != tl::Registrar<lay::PluginDeclaration>::end (); ++cls) {
+        cls->set_editable_enabled (false);
+      }
+      return true;
+
+    } else {
+      return false;
+    }
+  }
+
+  void implements_primary_mouse_modes (std::vector<std::pair<std::string, std::pair<std::string, int> > > &modes)
+  {
+    std::vector <std::string> mode_titles;
+    lay::LayoutView::intrinsic_mouse_modes (&mode_titles);
+
+    int mode_id = 0;
+    for (std::vector <std::string>::const_iterator t = mode_titles.begin (); t != mode_titles.end (); ++t, --mode_id) {
+      //  modes: pair(title, pair(insert_pos, id))
+      modes.push_back (std::make_pair (*t, std::make_pair ("edit_menu.mode_menu.end;@toolbar.end_modes", mode_id)));
+    }
+  }
+
+  lay::Plugin *create_plugin (db::Manager *manager, Dispatcher *, LayoutView *view) const
+  {
+    return new LayoutViewFunctions (manager, view);
+  }
+};
+
+static tl::RegisteredClass<lay::PluginDeclaration> config_decl (new LayoutViewPluginDeclaration (), -10, "LayoutViewPlugin");
+
+} // namespace lay
diff --git a/src/laybasic/laybasic/layLayoutViewFunctions.h b/src/laybasic/laybasic/layLayoutViewFunctions.h
new file mode 100644
index 000000000..15b2f3f56
--- /dev/null
+++ b/src/laybasic/laybasic/layLayoutViewFunctions.h
@@ -0,0 +1,171 @@
+
+/*
+
+  KLayout Layout Viewer
+  Copyright (C) 2006-2020 Matthias Koefferlein
+
+  This program is free software; you can redistribute it and/or modify
+  it under the terms of the GNU General Public License as published by
+  the Free Software Foundation; either version 2 of the License, or
+  (at your option) any later version.
+
+  This program is distributed in the hope that it will be useful,
+  but WITHOUT ANY WARRANTY; without even the implied warranty of
+  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+  GNU General Public License for more details.
+
+  You should have received a copy of the GNU General Public License
+  along with this program; if not, write to the Free Software
+  Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
+
+*/
+
+
+#ifndef HDR_layLayoutViewFunctions
+#define HDR_layLayoutViewFunctions
+
+#include "laybasicCommon.h"
+
+#include "layPlugin.h"
+#include "layDialogs.h"   //  For AlignCellOptions
+
+#include "dbTrans.h"
+#include "dbLayerProperties.h"
+
+namespace lay {
+
+class LayoutView;
+
+/**
+ *  @brief The layout view's functions implementation
+ */
+class LAYBASIC_PUBLIC LayoutViewFunctions
+  : public lay::Plugin
+{
+public:
+  /**
+   *  @brief Constructor
+   */
+  LayoutViewFunctions (db::Manager *manager, lay::LayoutView *view);
+
+  /** 
+   *  @brief Destructor
+   */
+  ~LayoutViewFunctions ();
+
+  //  Plugin interface implementation
+  void menu_activated (const std::string &symbol);
+
+  //  menu callbacks
+  void cm_new_layer ();
+  void cm_clear_layer ();
+  void cm_delete_layer ();
+  void cm_copy_layer ();
+  void cm_align_cell_origin ();
+  void cm_edit_layer ();
+  void cm_lay_convert_to_static ();
+  void cm_lay_flip_x ();
+  void cm_lay_flip_y ();
+  void cm_lay_rot_cw ();
+  void cm_lay_rot_ccw ();
+  void cm_lay_free_rot ();
+  void cm_lay_scale ();
+  void cm_lay_move ();
+  void cm_sel_flip_x ();
+  void cm_sel_flip_y ();
+  void cm_sel_rot_cw ();
+  void cm_sel_rot_ccw ();
+  void cm_sel_free_rot ();
+  void cm_sel_scale ();
+  void cm_sel_move ();
+  void cm_sel_move_to ();
+  void cm_sel_move_interactive ();
+
+  //  forwarded to the layer control panel
+  void cm_new_tab ();
+  void cm_rename_tab ();
+  void cm_remove_tab ();
+  void cm_select_all ();
+  void cm_make_valid ();
+  void cm_make_invalid ();
+  void cm_hide ();
+  void cm_hide_all ();
+  void cm_show ();
+  void cm_show_all ();
+  void cm_show_only ();
+  void cm_rename ();
+  void cm_delete ();
+  void cm_insert ();
+  void cm_group ();
+  void cm_ungroup ();
+  void cm_source ();
+  void cm_sort_by_name ();
+  void cm_sort_by_ild ();
+  void cm_sort_by_idl ();
+  void cm_sort_by_ldi ();
+  void cm_sort_by_dli ();
+  void cm_regroup_by_index ();
+  void cm_regroup_by_datatype ();
+  void cm_regroup_by_layer ();
+  void cm_regroup_flatten ();
+  void cm_expand_all ();
+  void cm_add_missing ();
+  void cm_remove_unused ();
+  void cm_layer_copy ();
+  void cm_layer_cut ();
+  void cm_layer_paste ();
+
+  //  forwarded to the cell control panel
+  void cm_cell_user_properties ();
+  void cm_cell_flatten ();
+  void cm_cell_rename ();
+  void cm_cell_replace ();
+  void cm_cell_delete ();
+  void cm_cell_select ();
+  void cm_open_current_cell ();
+  void cm_cell_hide ();
+  void cm_cell_show ();
+  void cm_cell_show_all ();
+  void cm_cell_copy ();
+  void cm_cell_cut ();
+  void cm_cell_paste ();
+  void cm_cell_convert_to_static ();
+
+protected:
+  lay::LayoutView *view ()
+  {
+    return mp_view;
+  }
+
+  db::Manager *manager ()
+  {
+    return mp_manager;
+  }
+
+  void do_cm_duplicate (bool interactive);
+  void do_cm_paste (bool interactive);
+  void cm_new_cell ();
+  void cm_reload ();
+
+  void do_transform (const db::DCplxTrans &tr);
+  void transform_layout (const db::DCplxTrans &tr);
+
+private:
+  lay::LayoutView *mp_view;
+  db::Manager *mp_manager;
+  db::LayerProperties m_new_layer_props;
+  db::DVector m_move_dist;
+  int m_move_to_origin_mode_x, m_move_to_origin_mode_y;
+  lay::AlignCellOptions m_align_cell_options;
+  int m_del_cell_mode;
+  int m_layer_hier_mode;
+  int m_duplicate_hier_mode;
+  bool m_clear_before;
+  int m_copy_cva, m_copy_cvr;
+  int m_copy_layera, m_copy_layerr;
+};
+
+}
+
+#endif
+
diff --git a/src/laybasic/laybasic/layPlugin.h b/src/laybasic/laybasic/layPlugin.h
index 2b74177dd..df042c998 100644
--- a/src/laybasic/laybasic/layPlugin.h
+++ b/src/laybasic/laybasic/layPlugin.h
@@ -54,6 +54,7 @@ class ViewService;
 class Editable;
 class Drawing;
 class TechnologyComponentProvider;
+class EditorOptionsPage;
 
 /**
  *  @brief The base class for configuration pages
@@ -234,7 +235,7 @@ public:
   {
     return std::vector<std::pair <std::string, ConfigPage *> > ();
   }
-  
+
   /**
    *  @brief The global configuration 
    *
@@ -317,7 +318,7 @@ public:
   }
 
   /**
-   *  @brief Fetch the menu objects for this plugin
+   *  @brief Fetches the menu objects for this plugin
    *
    *  The implementation of this method is supposed to call the base
    *  class'es "get_menu_entries" method and add it's own entries.
@@ -328,7 +329,7 @@ public:
   }
 
   /**
-   *  @brief Create a plugin object of the respective kind
+   *  @brief Creates a plugin object of the respective kind
    *
    *  This method may return 0 for "dummy" plugins that just register menu entries
    *  or configuration options.
@@ -339,7 +340,7 @@ public:
   }
 
   /**
-   *  @brief Tell if the plugin implements the "lay::Editable" interface
+   *  @brief Tells if the plugin implements the "lay::Editable" interface
    *
    *  This method is supposed to return true if the plugin implements the 
    *  lay::Editable interface and wants to be listed as an "edit" mode in the
@@ -350,9 +351,22 @@ public:
   {
     return false;
   }
-  
+
   /**
-   *  @brief Tell if the plugin implements a "lay::ViewService" active mouse mode
+   *  @brief Gets the editor options pages
+   *
+   *  Editor options pages are shown in the editor options dockable tool widget. Each plugin can create such pages
+   *  and these will be shown in tabs inside this widget.
+   *
+   *  The new pages are returned in the "pages" vector. The layout view will take ownership of these pages.
+   */
+  virtual void get_editor_options_pages (std::vector<lay::EditorOptionsPage *> & /*pages*/, lay::LayoutView * /*view*/, lay::Dispatcher * /*dispatcher*/) const
+  {
+    //  .. no pages in the default implementation ..
+  }
+
+  /**
+   *  @brief Tells if the plugin implements a "lay::ViewService" active mouse mode
    *
    *  This method is supposed to return true if the plugin implements the 
    *  lay::ViewService interface and wants to be listed as an mouse mode in the
diff --git a/src/laybasic/laybasic/layProperties.h b/src/laybasic/laybasic/layProperties.h
index 6c918b8c0..9eedcdafc 100644
--- a/src/laybasic/laybasic/layProperties.h
+++ b/src/laybasic/laybasic/layProperties.h
@@ -48,6 +48,8 @@ class Editable;
 class LAYBASIC_PUBLIC PropertiesPage
   : public QFrame
 {
+Q_OBJECT
+
 public:
   /**
    *  @brief The constructor attaching the properties page to a parent widget
@@ -140,7 +142,7 @@ public:
    */
   virtual void operator++ () = 0;
 
-  /** 
+  /**
    *  @brief Update the display
    *
    *  This method is called by the dialog to transfer data from the
@@ -196,7 +198,7 @@ public:
    *  If nothing was changed, the objects may be left untouched.
    *  The dialog will start a transaction on the manager object.
    */
-  virtual void apply_to_all () 
+  virtual void apply_to_all (bool /*relative*/)
   {
     //  default implementation is empty.
   }
@@ -219,6 +221,12 @@ public:
     return mp_manager;
   }
 
+signals:
+  /**
+   *  @brief This signal is emitted if a value has been changed
+   */
+  void edited ();
+
 private:
   db::Manager *mp_manager;
   lay::Editable *mp_editable;
diff --git a/src/laybasic/laybasic/layPropertiesDialog.cc b/src/laybasic/laybasic/layPropertiesDialog.cc
index 31bdb36ce..cc40f5aba 100644
--- a/src/laybasic/laybasic/layPropertiesDialog.cc
+++ b/src/laybasic/laybasic/layPropertiesDialog.cc
@@ -35,7 +35,7 @@ namespace lay
 
 PropertiesDialog::PropertiesDialog (QWidget * /*parent*/, db::Manager *manager, lay::Editables *editables)
   : QDialog (0 /*parent*/),
-    mp_manager (manager), mp_editables (editables), m_index (-1)
+    mp_manager (manager), mp_editables (editables), m_index (-1), m_auto_applied (false), m_transaction_id (0)
 {
   mp_editables->enable_edits (false);
 
@@ -49,6 +49,7 @@ PropertiesDialog::PropertiesDialog (QWidget * /*parent*/, db::Manager *manager,
     mp_properties_pages.push_back (e->properties_page (mp_manager, content_frame));
     if (mp_properties_pages.back ()) {
       mp_stack->addWidget (mp_properties_pages.back ());
+      connect (mp_properties_pages.back (), SIGNAL (edited ()), this, SLOT (apply ()));
     }
   }
 
@@ -63,8 +64,8 @@ PropertiesDialog::PropertiesDialog (QWidget * /*parent*/, db::Manager *manager,
   content_frame->setLayout (mp_stack);
 
   //  disable the apply button for first ..
-  apply_button->setEnabled (false);
-  apply_to_all_button->setEnabled (false);
+  apply_to_all_cbx->setEnabled (false);
+  relative_cbx->setEnabled (false);
   ok_button->setEnabled (false);
 
   //  as a proposal, the start button can be enabled in most cases
@@ -86,22 +87,28 @@ PropertiesDialog::PropertiesDialog (QWidget * /*parent*/, db::Manager *manager,
 
   //  if at end disable the "Next" button and return (this may only happen at the first call)
   if (m_index >= int (mp_properties_pages.size ())) {
+
     next_button->setEnabled (false);
     mp_stack->setCurrentWidget (dummy);
-    apply_button->setEnabled (false);
-    apply_to_all_button->setEnabled (false);
+    apply_to_all_cbx->setEnabled (false);
+    apply_to_all_cbx->setChecked (false);
+    relative_cbx->setEnabled (false);
+    relative_cbx->setChecked (false);
     ok_button->setEnabled (false);
+
   } else {
+
     next_button->setEnabled (any_next ());
     mp_properties_pages [m_index]->update ();
     mp_stack->setCurrentWidget (mp_properties_pages [m_index]);
-    apply_button->setEnabled (! mp_properties_pages [m_index]->readonly ());
-    apply_to_all_button->setEnabled (! mp_properties_pages [m_index]->readonly () && mp_properties_pages [m_index]->can_apply_to_all ());
+    apply_to_all_cbx->setEnabled (! mp_properties_pages [m_index]->readonly () && mp_properties_pages [m_index]->can_apply_to_all ());
+    apply_to_all_cbx->setChecked (false);
+    relative_cbx->setEnabled (apply_to_all_cbx->isEnabled () && apply_to_all_cbx->isChecked ());
+    relative_cbx->setChecked (true);
     ok_button->setEnabled (! mp_properties_pages [m_index]->readonly ());
+
   }
 
-  connect (apply_button, SIGNAL (clicked ()), this, SLOT (apply_pressed ()));
-  connect (apply_to_all_button, SIGNAL (clicked ()), this, SLOT (apply_to_all_pressed ()));
   connect (ok_button, SIGNAL (clicked ()), this, SLOT (ok_pressed ()));
   connect (cancel_button, SIGNAL (clicked ()), this, SLOT (cancel_pressed ()));
   connect (prev_button, SIGNAL (clicked ()), this, SLOT (prev_pressed ()));
@@ -130,8 +137,9 @@ PropertiesDialog::next_pressed ()
 BEGIN_PROTECTED
 
   if (! mp_properties_pages [m_index]->readonly ()) {
-    db::Transaction t (mp_manager, tl::to_string (QObject::tr ("Apply changes")));
+    db::Transaction t (mp_manager, tl::to_string (QObject::tr ("Apply changes")), m_transaction_id);
     mp_properties_pages [m_index]->apply ();
+    m_transaction_id = t.id ();
   }
 
   //  advance the current entry
@@ -157,8 +165,8 @@ BEGIN_PROTECTED
 
   prev_button->setEnabled (true);
   next_button->setEnabled (any_next ());
-  apply_button->setEnabled (! mp_properties_pages [m_index]->readonly ());
-  apply_to_all_button->setEnabled (! mp_properties_pages [m_index]->readonly () && mp_properties_pages [m_index]->can_apply_to_all ());
+  apply_to_all_cbx->setEnabled (! mp_properties_pages [m_index]->readonly () && mp_properties_pages [m_index]->can_apply_to_all ());
+  relative_cbx->setEnabled (apply_to_all_cbx->isEnabled () && apply_to_all_cbx->isChecked ());
   ok_button->setEnabled (! mp_properties_pages [m_index]->readonly ());
   mp_properties_pages [m_index]->update ();
 
@@ -171,8 +179,9 @@ PropertiesDialog::prev_pressed ()
 BEGIN_PROTECTED
 
   if (! mp_properties_pages [m_index]->readonly ()) {
-    db::Transaction t (mp_manager, tl::to_string (QObject::tr ("Apply changes")));
+    db::Transaction t (mp_manager, tl::to_string (QObject::tr ("Apply changes")), m_transaction_id);
     mp_properties_pages [m_index]->apply ();
+    m_transaction_id = t.id ();
   }
 
   if (mp_properties_pages [m_index]->at_begin ()) {
@@ -200,8 +209,8 @@ BEGIN_PROTECTED
 
   next_button->setEnabled (true);
   prev_button->setEnabled (any_prev ());
-  apply_button->setEnabled (! mp_properties_pages [m_index]->readonly ());
-  apply_to_all_button->setEnabled (! mp_properties_pages [m_index]->readonly () && mp_properties_pages [m_index]->can_apply_to_all ());
+  apply_to_all_cbx->setEnabled (! mp_properties_pages [m_index]->readonly () && mp_properties_pages [m_index]->can_apply_to_all ());
+  relative_cbx->setEnabled (apply_to_all_cbx->isEnabled () && apply_to_all_cbx->isChecked ());
   ok_button->setEnabled (! mp_properties_pages [m_index]->readonly ());
   mp_properties_pages [m_index]->update ();
 
@@ -251,28 +260,27 @@ PropertiesDialog::any_prev () const
   return (index >= 0);
 }
 
-void 
-PropertiesDialog::apply_to_all_pressed ()
+void
+PropertiesDialog::apply ()
 {
 BEGIN_PROTECTED
 
-  db::Transaction t (mp_manager, tl::to_string (QObject::tr ("Apply changes to all")));
+  db::Transaction t (mp_manager, tl::to_string (QObject::tr ("Auto-apply changes")), m_transaction_id);
 
-  mp_properties_pages [m_index]->apply_to_all ();
-  mp_properties_pages [m_index]->update ();
+  try {
 
-END_PROTECTED
-}
+    if (apply_to_all_cbx->isChecked () && mp_properties_pages [m_index]->can_apply_to_all ()) {
+      mp_properties_pages [m_index]->apply_to_all (relative_cbx->isChecked ());
+    } else {
+      mp_properties_pages [m_index]->apply ();
+    }
+    mp_properties_pages [m_index]->update ();
 
-void 
-PropertiesDialog::apply_pressed ()
-{
-BEGIN_PROTECTED
+  } catch (tl::Exception &) {
+    //  we assume the page somehow indicates the error and does not apply the values
+  }
 
-  db::Transaction t (mp_manager, tl::to_string (QObject::tr ("Apply changes")));
-
-  mp_properties_pages [m_index]->apply ();
-  mp_properties_pages [m_index]->update ();
+  m_transaction_id = t.id ();
 
 END_PROTECTED
 }
@@ -280,6 +288,17 @@ END_PROTECTED
 void 
 PropertiesDialog::cancel_pressed ()
 {
+  //  undo whatever we've done so far
+  if (m_transaction_id > 0) {
+
+    //  because undo does not maintain a valid selection we clear it
+    mp_editables->clear_selection ();
+
+    mp_manager->undo ();
+    m_transaction_id = 0;
+
+  }
+
   //  make sure that the property pages are no longer used ..
   disconnect ();
   //  close the dialog
@@ -293,11 +312,13 @@ BEGIN_PROTECTED
 
   if (! mp_properties_pages [m_index]->readonly ()) {
 
-    db::Transaction t (mp_manager, tl::to_string (QObject::tr ("Apply changes")));
+    db::Transaction t (mp_manager, tl::to_string (QObject::tr ("Apply changes")), m_transaction_id);
 
     mp_properties_pages [m_index]->apply ();
     mp_properties_pages [m_index]->update ();
 
+    m_transaction_id = t.id ();
+
   }
 
   //  make sure that the property pages are no longer used ..
diff --git a/src/laybasic/laybasic/layPropertiesDialog.h b/src/laybasic/laybasic/layPropertiesDialog.h
index c06efcb69..26a342dad 100644
--- a/src/laybasic/laybasic/layPropertiesDialog.h
+++ b/src/laybasic/laybasic/layPropertiesDialog.h
@@ -32,12 +32,11 @@
 #include <QStatusBar>
 #include <QMessageBox>
 
+#include <dbManager.h>
+
 #include "ui_PropertiesDialog.h"
 
-namespace db
-{
-  class Manager;
-}
+#include <memory>
 
 class QStackedLayout;
 
@@ -74,13 +73,15 @@ public:
   ~PropertiesDialog ();
 
 private:
-  std::vector <lay::PropertiesPage *> mp_properties_pages;
+  std::vector<lay::PropertiesPage *> mp_properties_pages;
   db::Manager *mp_manager;
   lay::Editables *mp_editables;
   int m_index;
   QStackedLayout *mp_stack;
   lay::MainWindow *mp_mw;
   size_t m_objects, m_current_object;
+  bool m_auto_applied;
+  db::Manager::transaction_id_t m_transaction_id;
 
   void disconnect ();
   bool any_prev () const;
@@ -88,10 +89,9 @@ private:
   void update_title ();
 
 public slots:
+  void apply ();
   void next_pressed ();
   void prev_pressed ();
-  void apply_pressed ();
-  void apply_to_all_pressed ();
   void cancel_pressed ();
   void ok_pressed ();
 
diff --git a/src/laybasic/laybasic/layQtTools.cc b/src/laybasic/laybasic/layQtTools.cc
index 4d174ade4..96d44fe05 100644
--- a/src/laybasic/laybasic/layQtTools.cc
+++ b/src/laybasic/laybasic/layQtTools.cc
@@ -31,6 +31,7 @@
 #include <QSplitter>
 #include <QWidget>
 #include <QLabel>
+#include <QPalette>
 
 #include <stdio.h>
 
@@ -159,5 +160,24 @@ restore_dialog_state (QWidget *dialog, const std::string &s, bool with_section_s
   }
 }
 
+void
+indicate_error (QWidget *le, const tl::Exception *ex)
+{
+  //  by the way, update the foreground color of the cell edit box as well (red, if not valid)
+  QPalette pl = le->palette ();
+  if (ex) {
+    pl.setColor (QPalette::Active, QPalette::Text, Qt::red);
+    pl.setColor (QPalette::Active, QPalette::Base, QColor (Qt::red).lighter (180));
+    le->setToolTip (tl::to_qstring (ex->msg ()));
+  } else {
+    QWidget *pw = dynamic_cast<QWidget *> (le->parent ());
+    tl_assert (pw != 0);
+    pl.setColor (QPalette::Active, QPalette::Text, pw->palette ().color (QPalette::Text));
+    pl.setColor (QPalette::Active, QPalette::Base, pw->palette ().color (QPalette::Base));
+    le->setToolTip (QString ());
+  }
+  le->setPalette (pl);
+}
+
 }
 
diff --git a/src/laybasic/laybasic/layQtTools.h b/src/laybasic/laybasic/layQtTools.h
index 36afc666c..49232c9d6 100644
--- a/src/laybasic/laybasic/layQtTools.h
+++ b/src/laybasic/laybasic/layQtTools.h
@@ -32,6 +32,11 @@ class QLabel;
 class QWidget;
 class QObject;
 
+namespace tl
+{
+  class Exception;
+}
+
 namespace lay
 {
 
@@ -62,6 +67,14 @@ LAYBASIC_PUBLIC void activate_modal_help_links (QLabel *label);
  */
 LAYBASIC_PUBLIC void register_help_handler (QObject *object, const char *slot, const char *modal_slot);
 
+/**
+ *  @brief Configures a QLineEdit or other widget to indicate an error
+ *
+ *  When a non-null ex pointer is passed, the background will be turned red
+ *  and the exception's text will be used as tooltip. Use this function with
+ *  a null ex pointer to clear the error condition.
+ */
+LAYBASIC_PUBLIC void indicate_error (QWidget *le, const tl::Exception *ex);
 
 } // namespace lay
 
diff --git a/src/laybasic/laybasic/laySelector.cc b/src/laybasic/laybasic/laySelector.cc
index ffe76e411..d1e5d1425 100644
--- a/src/laybasic/laybasic/laySelector.cc
+++ b/src/laybasic/laybasic/laySelector.cc
@@ -74,10 +74,7 @@ void
 SelectionService::deactivated ()
 {
   mp_view->clear_transient_selection ();
-  if (mp_box) {
-    delete mp_box;
-    mp_box = 0;
-  }
+  reset_box ();
 }
 
 void 
@@ -102,7 +99,20 @@ SelectionService::timeout ()
   mp_view->transient_select (m_hover_point);
 }
 
-bool 
+void
+SelectionService::reset_box ()
+{
+  if (mp_box) {
+
+    widget ()->ungrab_mouse (this);
+
+    delete mp_box;
+    mp_box = 0;
+
+  }
+}
+
+bool
 SelectionService::wheel_event (int /*delta*/, bool /*horizonal*/, const db::DPoint & /*p*/, unsigned int /*buttons*/, bool /*prio*/)
 {
   return false;
@@ -115,19 +125,31 @@ SelectionService::enter_event (bool /*prio*/)
   return false;
 }
 
-bool 
-SelectionService::leave_event (bool /*prio*/) 
+bool
+SelectionService::leave_event (bool prio)
 {
   m_mouse_in_window = false;
+
   hover_reset ();
+
+  if (prio) {
+    reset_box ();
+  }
+
   return false;
 }
 
 bool 
-SelectionService::mouse_move_event (const db::DPoint &p, unsigned int /*buttons*/, bool prio) 
+SelectionService::mouse_move_event (const db::DPoint &p, unsigned int buttons, bool prio)
 {
   if (prio) {
 
+    m_current_position = p;
+
+    if ((buttons & LeftButton) == 0) {
+      reset_box ();
+    }
+
     if (mp_box) {
       m_p2 = p;
       mp_box->set_points (m_p1, m_p2);
@@ -138,6 +160,7 @@ SelectionService::mouse_move_event (const db::DPoint &p, unsigned int /*buttons*
     }
 
   }
+
   return false;
 }
 
@@ -145,6 +168,11 @@ bool
 SelectionService::mouse_double_click_event (const db::DPoint & /*p*/, unsigned int buttons, bool prio)
 {
   hover_reset ();
+
+  if (prio) {
+    reset_box ();
+  }
+
   if (prio && (buttons & lay::LeftButton) != 0) {
     mp_view->show_properties (QApplication::activeWindow ());
     return true;
@@ -157,11 +185,18 @@ bool
 SelectionService::mouse_press_event (const db::DPoint &p, unsigned int buttons, bool prio)
 {
   hover_reset ();
-  if (prio && ! mp_box && (buttons & lay::LeftButton) != 0) {
-    mp_view->stop_redraw (); // TODO: how to restart if selection is aborted?
-    m_buttons = buttons;
-    begin (p);
-    return true;
+
+  if (prio) {
+
+    reset_box ();
+
+    if ((buttons & lay::LeftButton) != 0) {
+      mp_view->stop_redraw (); // TODO: how to restart if selection is aborted?
+      m_buttons = buttons;
+      begin (p);
+      return true;
+    }
+
   }
 
   return false;
@@ -170,7 +205,11 @@ SelectionService::mouse_press_event (const db::DPoint &p, unsigned int buttons,
 bool 
 SelectionService::mouse_click_event (const db::DPoint &p, unsigned int buttons, bool prio) 
 { 
-  if (prio && mp_view && widget ()->mouse_event_viewport ().contains (p) && (buttons & lay::LeftButton) != 0) { 
+  if (prio) {
+    reset_box ();
+  }
+
+  if (prio && mp_view && widget ()->mouse_event_viewport ().contains (p) && (buttons & lay::LeftButton) != 0) {
 
     lay::Editable::SelectionMode mode = lay::Editable::Replace;
     bool shift = ((buttons & lay::ShiftButton) != 0);
@@ -211,12 +250,10 @@ bool
 SelectionService::mouse_release_event (const db::DPoint & /*p*/, unsigned int /*buttons*/, bool prio) 
 { 
   hover_reset ();
+
   if (prio && mp_box) {
 
-    widget ()->ungrab_mouse (this);
-
-    delete mp_box;
-    mp_box = 0;
+    reset_box ();
 
     if (mp_view) { 
 
diff --git a/src/laybasic/laybasic/laySelector.h b/src/laybasic/laybasic/laySelector.h
index ddf60c6f8..e302d70f4 100644
--- a/src/laybasic/laybasic/laySelector.h
+++ b/src/laybasic/laybasic/laySelector.h
@@ -25,6 +25,8 @@
 #ifndef HDR_laySelector
 #define HDR_laySelector
 
+#include "laybasicCommon.h"
+
 #include "layViewObject.h"
 #include "layEditable.h"
 
@@ -37,7 +39,7 @@ class RubberBox;
 class LayoutView;
 class LayoutCanvas;
 
-class SelectionService
+class LAYBASIC_PUBLIC SelectionService
   : public QObject,
     public lay::ViewService
 {
@@ -77,6 +79,7 @@ private:
   virtual void deactivated ();
 
   db::DPoint m_p1, m_p2;
+  db::DPoint m_current_position;
   lay::LayoutView *mp_view;
   lay::RubberBox *mp_box;
   unsigned int m_color;
@@ -86,6 +89,8 @@ private:
   bool m_hover_wait;
   db::DPoint m_hover_point;
   bool m_mouse_in_window;
+
+  void reset_box ();
 };
 
 }
diff --git a/src/laybasic/laybasic/laySnap.cc b/src/laybasic/laybasic/laySnap.cc
index 04de10a99..841468c63 100644
--- a/src/laybasic/laybasic/laySnap.cc
+++ b/src/laybasic/laybasic/laySnap.cc
@@ -726,7 +726,7 @@ private:
   bool m_directed;
 };
 
-static std::pair <bool, db::DPoint>
+static PointSnapToObjectResult
 do_obj_snap (lay::LayoutView *view, const db::DPoint &pt, const db::DVector &grid, double snap_range, const std::vector <db::DEdge> &cutlines)
 {
   db::DPoint dp (pt);
@@ -753,25 +753,45 @@ do_obj_snap (lay::LayoutView *view, const db::DPoint &pt, const db::DVector &gri
     }
   }
 
-  if (finder.any () && anyp) {
-    //  if both the projection and the finder are sucessful, decide by a heuristic criterion which to take
-    //  (the projection gets a penalty (of the snap range) to make it count less than the finder's choice)
-    //  This avoids extreme distortions of the ruler due to projection on long edges.
-    if ((dp.distance (closest) + snap_range) * 5.0 < dp.distance (finder.get_found ())) {
-      return std::make_pair (false, closest);
-    } else {
-      return std::make_pair (true, finder.get_found ());
-    }
+  //  if both the projection and the finder are sucessful, decide by a heuristic criterion which to take
+  //  (the projection gets a penalty (of the snap range) to make it count less than the finder's choice)
+  //  This avoids extreme distortions of the ruler due to projection on long edges.
+  if (finder.any () && anyp && (dp.distance (closest) + snap_range) * 5.0 < dp.distance (finder.get_found ())) {
+
+    PointSnapToObjectResult res;
+    res.snapped_point = closest;
+    return res;
+
   } else if (finder.any ()) {
-    return std::make_pair (true, finder.get_found ());
+
+    PointSnapToObjectResult res;
+    res.snapped_point = finder.get_found ();
+    res.object_ref = finder.get_found_edge ();
+    if (finder.is_vertex ()) {
+      res.object_snap = PointSnapToObjectResult::ObjectVertex;
+    } else if (finder.has_found_edge ()) {
+      res.object_snap = PointSnapToObjectResult::ObjectEdge;
+    } else {
+      res.object_snap = PointSnapToObjectResult::ObjectUnspecific;
+    }
+    return res;
+
   } else if (anyp) {
-    return std::make_pair (false, closest);
+
+    PointSnapToObjectResult res;
+    res.snapped_point = closest;
+    return res;
+
   } else {
-    return std::make_pair (false, dp);
+
+    PointSnapToObjectResult res;
+    res.snapped_point = dp;
+    return res;
+
   }
 }
 
-std::pair <bool, db::DEdge>
+static TwoPointSnapToObjectResult
 do_obj_snap2 (lay::LayoutView *view, const db::DPoint &pt1, const db::DPoint &pt2, const db::DVector &grid, double min_search_range, double max_search_range, const std::vector <db::DEdge> &cutlines)
 {
   db::DPoint dp1 (pt1);
@@ -828,15 +848,41 @@ do_obj_snap2 (lay::LayoutView *view, const db::DPoint &pt1, const db::DPoint &pt
 
         finder2.find (view, sr2);
         if (finder2.any_exact ()) {
+
           db::DPoint p2 = finder2.get_found ();
-          return std::make_pair (true, db::DEdge (p1, p2));
+
+          TwoPointSnapToObjectResult res;
+          res.any = true;
+          res.first = p1;
+          res.second = p2;
+
+          res.object_ref_first = finder.get_found_edge ();
+          if (finder.is_vertex ()) {
+            res.object_snap_first = TwoPointSnapToObjectResult::ObjectVertex;
+          } else if (finder.has_found_edge ()) {
+            res.object_snap_first = TwoPointSnapToObjectResult::ObjectEdge;
+          } else {
+            res.object_snap_first = TwoPointSnapToObjectResult::ObjectUnspecific;
+          }
+
+          res.object_ref_second = finder2.get_found_edge ();
+          if (finder2.is_vertex ()) {
+            res.object_snap_second = TwoPointSnapToObjectResult::ObjectVertex;
+          } else if (finder2.has_found_edge ()) {
+            res.object_snap_second = TwoPointSnapToObjectResult::ObjectEdge;
+          } else {
+            res.object_snap_second = TwoPointSnapToObjectResult::ObjectUnspecific;
+          }
+
+          return res;
+
         }
 
         sr2 *= 2.0;
 
       }
 
-      return std::make_pair (false, db::DEdge ());
+      return TwoPointSnapToObjectResult ();
 
     }
 
@@ -844,7 +890,7 @@ do_obj_snap2 (lay::LayoutView *view, const db::DPoint &pt1, const db::DPoint &pt
 
   }
 
-  return std::make_pair (false, db::DEdge ());
+  return TwoPointSnapToObjectResult ();
 }
 
 static void
@@ -868,13 +914,13 @@ make_cutlines (lay::angle_constraint_type snap_mode, const db::DPoint &p1, std::
   }
 }
 
-std::pair <bool, db::DPoint>
+PointSnapToObjectResult
 obj_snap (lay::LayoutView *view, const db::DPoint &pt, const db::DVector &grid, double snap_range)
 {
   return do_obj_snap (view, pt, grid, snap_range, std::vector<db::DEdge> ());
 }
 
-std::pair <bool, db::DPoint>
+PointSnapToObjectResult
 obj_snap (lay::LayoutView *view, const db::DPoint &p1, const db::DPoint &p2, const db::DVector &grid, lay::angle_constraint_type snap_mode, double snap_range)
 {
   std::vector <db::DEdge> cutlines;
@@ -882,19 +928,19 @@ obj_snap (lay::LayoutView *view, const db::DPoint &p1, const db::DPoint &p2, con
   return do_obj_snap (view, p2, grid, snap_range, cutlines);
 }
 
-std::pair <bool, db::DEdge>
+TwoPointSnapToObjectResult
 obj_snap2 (lay::LayoutView *view, const db::DPoint &pt, const db::DVector &grid, double min_search_range, double max_search_range)
 {
   return obj_snap2 (view, pt, pt, grid, min_search_range, max_search_range);
 }
 
-std::pair <bool, db::DEdge>
+TwoPointSnapToObjectResult
 obj_snap2 (lay::LayoutView *view, const db::DPoint &pt, const db::DVector &grid, lay::angle_constraint_type ac, double min_search_range, double max_search_range)
 {
   return obj_snap2 (view, pt, pt, grid, ac, min_search_range, max_search_range);
 }
 
-std::pair <bool, db::DEdge>
+TwoPointSnapToObjectResult
 obj_snap2 (lay::LayoutView *view, const db::DPoint &pt1, const db::DPoint &pt2, const db::DVector &grid, double min_search_range, double max_search_range)
 {
   db::DPoint dp1 = lay::snap_xy (pt1, grid);
@@ -903,7 +949,7 @@ obj_snap2 (lay::LayoutView *view, const db::DPoint &pt1, const db::DPoint &pt2,
   return do_obj_snap2 (view, dp1, dp2, db::DVector (), min_search_range, max_search_range, std::vector<db::DEdge> ());
 }
 
-std::pair <bool, db::DEdge>
+TwoPointSnapToObjectResult
 obj_snap2 (lay::LayoutView *view, const db::DPoint &pt1, const db::DPoint &pt2, const db::DVector &grid, lay::angle_constraint_type snap_mode, double min_search_range, double max_search_range)
 {
   db::DPoint dp1 = lay::snap_xy (pt1, grid);
diff --git a/src/laybasic/laybasic/laySnap.h b/src/laybasic/laybasic/laySnap.h
index 8ac286b24..b2a1b3645 100644
--- a/src/laybasic/laybasic/laySnap.h
+++ b/src/laybasic/laybasic/laySnap.h
@@ -108,6 +108,36 @@ namespace lay
    */
   LAYBASIC_PUBLIC std::pair<db::DPoint, db::DPoint> snap (const db::DPoint &p1, const db::DPoint &p2, db::DCoord grid);
 
+  /**
+   *  @brief A structure describing the snap result for a point-wise snap
+   */
+  struct LAYBASIC_PUBLIC PointSnapToObjectResult
+  {
+    enum ObjectSnap {
+      NoObject = 0,
+      ObjectVertex,
+      ObjectEdge,
+      ObjectUnspecific
+    };
+
+    PointSnapToObjectResult () : object_snap (NoObject) { }
+
+    /**
+     *  @brief The result of the snap
+     */
+    db::DPoint snapped_point;
+
+    /**
+     *  @brief Indicates whether and how the point was snapped to an object
+     */
+    ObjectSnap object_snap;
+
+    /**
+     *  @brief Indicates the edge the point was snapped against unless in NoObject mode
+     */
+    db::DEdge object_ref;
+  };
+
   /**
    *  @brief combined grid-, projection- and object snapping provided to implementing "magnetic features"
    *
@@ -115,17 +145,14 @@ namespace lay
    *  to an object edge or point. It will use a heuristics to determine
    *  what criterion is applied if a conflict is detected.
    *
-   *  The function will return a pair of the "stiffness" flag and the resulting point. The
-   *  "stiffness" is a measure if the result point can be moved if another snap will be applied.
-   *  It is true if the point is not intended to be moved further, i.e. because it snapped to 
-   *  a grid point or a object vertex.
+   *  The function will return a PointSnapToObjectResult object.
    *
    *  @param view The layout view used for object snapping. Can be 0 to disable object snapping
    *  @param pt The point to snap
    *  @param grid Either (0,0) to disable grid snapping or a (gx,gy) value for the (potentially anisotropic grid)
    *  @param snap_range The search range for objects 
    */
-  LAYBASIC_PUBLIC std::pair <bool, db::DPoint> obj_snap (lay::LayoutView *view, const db::DPoint &pt, const db::DVector &grid, double snap_range);
+  LAYBASIC_PUBLIC PointSnapToObjectResult obj_snap (lay::LayoutView *view, const db::DPoint &pt, const db::DVector &grid, double snap_range);
 
   /**
    *  @brief combined grid-, projection- and object snapping provided to implementing "magnetic features"
@@ -133,7 +160,45 @@ namespace lay
    *  This is a convenience method that creates the projection axes from a reference point and an angle mode.
    *  "pr" is the reference point, "pt" is the point to snap.
    */
-  LAYBASIC_PUBLIC std::pair <bool, db::DPoint> obj_snap (lay::LayoutView *view, const db::DPoint &pr, const db::DPoint &pt, const db::DVector &grid, lay::angle_constraint_type ac, double snap_range);
+  LAYBASIC_PUBLIC PointSnapToObjectResult obj_snap (lay::LayoutView *view, const db::DPoint &pr, const db::DPoint &pt, const db::DVector &grid, lay::angle_constraint_type ac, double snap_range);
+
+  /**
+   *  @brief A structure describing the snap result for a two-sided object snap (distance measurement)
+   */
+  struct LAYBASIC_PUBLIC TwoPointSnapToObjectResult
+  {
+    enum ObjectSnap {
+      NoObject = 0,
+      ObjectVertex,
+      ObjectEdge,
+      ObjectUnspecific
+    };
+
+    TwoPointSnapToObjectResult () : any (false), object_snap_first (NoObject), object_snap_second (NoObject) { }
+
+    /**
+     *  @brief Indicates whether the two-sided snap was successful
+     */
+    bool any;
+
+    /**
+     *  @brief The result of the snap
+     *  Two values are provided for the first and second snap.
+     */
+    db::DPoint first, second;
+
+    /**
+     *  @brief Indicates whether and how the point was snapped to an object
+     *  Two values are provided for the first and second snap.
+     */
+    ObjectSnap object_snap_first, object_snap_second;
+
+    /**
+     *  @brief Indicates the edge the point was snapped against unless in NoObject mode
+     *  Two values are provided for the first and second snap.
+     */
+    db::DEdge object_ref_first, object_ref_second;
+  };
 
   /**
    *  @brief Same than obj_snap, but delivers two points on two opposite sides of the initial point
@@ -141,7 +206,7 @@ namespace lay
    *  This method basically implements "auto measure". The first value of the returned pair
    *  is true if such an edge could be found. Otherwise it's false.
    */
-  LAYBASIC_PUBLIC std::pair <bool, db::DEdge> obj_snap2 (lay::LayoutView *view, const db::DPoint &pt, const db::DVector &grid, double min_search_range, double max_search_range);
+  LAYBASIC_PUBLIC TwoPointSnapToObjectResult obj_snap2 (lay::LayoutView *view, const db::DPoint &pt, const db::DVector &grid, double min_search_range, double max_search_range);
 
   /**
    *  @brief Same than obj_snap, but delivers two points on two opposite sides of the initial points
@@ -151,14 +216,14 @@ namespace lay
    *
    *  This version accepts two points defining different search regions for first and second edge.
    */
-  LAYBASIC_PUBLIC std::pair <bool, db::DEdge> obj_snap2 (lay::LayoutView *view, const db::DPoint &pt1, const db::DPoint &pt2, const db::DVector &grid, double min_search_range, double max_search_range);
+  LAYBASIC_PUBLIC TwoPointSnapToObjectResult obj_snap2 (lay::LayoutView *view, const db::DPoint &pt1, const db::DPoint &pt2, const db::DVector &grid, double min_search_range, double max_search_range);
 
   /**
    *  @brief Same than the previous obj_snap2, but allows specification of an angle constraint
    *
    *  Measurements will be confined to the direction specified.
    */
-  LAYBASIC_PUBLIC std::pair <bool, db::DEdge> obj_snap2 (lay::LayoutView *view, const db::DPoint &pt, const db::DVector &grid, lay::angle_constraint_type ac, double min_search_range, double max_search_range);
+  LAYBASIC_PUBLIC TwoPointSnapToObjectResult obj_snap2 (lay::LayoutView *view, const db::DPoint &pt, const db::DVector &grid, lay::angle_constraint_type ac, double min_search_range, double max_search_range);
 
   /**
    *  @brief Same than the previous obj_snap2, but allows specification of an angle constraint
@@ -167,7 +232,7 @@ namespace lay
    *
    *  This version accepts two points defining different search regions for first and second edge.
    */
-  LAYBASIC_PUBLIC std::pair <bool, db::DEdge> obj_snap2 (lay::LayoutView *view, const db::DPoint &pt1, const db::DPoint &pt2, const db::DVector &grid, lay::angle_constraint_type ac, double min_search_range, double max_search_range);
+  LAYBASIC_PUBLIC TwoPointSnapToObjectResult obj_snap2 (lay::LayoutView *view, const db::DPoint &pt1, const db::DPoint &pt2, const db::DVector &grid, lay::angle_constraint_type ac, double min_search_range, double max_search_range);
 
   /**
    *  @brief Reduce a given vector according to the angle constraint
diff --git a/src/laybasic/laybasic/layViewObject.cc b/src/laybasic/laybasic/layViewObject.cc
index cc68a61f8..1ba1e5dfd 100644
--- a/src/laybasic/laybasic/layViewObject.cc
+++ b/src/laybasic/laybasic/layViewObject.cc
@@ -73,6 +73,10 @@ CellDragDropData::serialized () const
   stream << (quintptr) mp_library;
   stream << m_cell_index;
   stream << m_is_pcell;
+  stream << int (m_pcell_params.size ());
+  for (std::vector<tl::Variant>::const_iterator i = m_pcell_params.begin (); i != m_pcell_params.end (); ++i) {
+    stream << tl::to_qstring (i->to_parsable_string ());
+  }
 
   return data;
 }
@@ -94,6 +98,19 @@ CellDragDropData::deserialize (const QByteArray &ba)
     mp_library = reinterpret_cast <const db::Library *> (p);
     stream >> m_cell_index;
     stream >> m_is_pcell;
+
+    m_pcell_params.clear ();
+    int n = 0;
+    stream >> n;
+    while (n-- > 0) {
+      QString s;
+      stream >> s;
+      std::string stl_s = tl::to_string (s);
+      tl::Extractor ex (stl_s.c_str ());
+      m_pcell_params.push_back (tl::Variant ());
+      ex.read (m_pcell_params.back ());
+    }
+
     return true;
 
   } else {
@@ -272,6 +289,7 @@ ViewObjectWidget::ViewObjectWidget (QWidget *parent, const char *name)
     m_mouse_pressed_state (false),
     m_mouse_buttons (0),
     m_in_mouse_move (false),
+    m_mouse_inside (false),
     m_cursor (lay::Cursor::none),
     m_default_cursor (lay::Cursor::none)
 {
@@ -363,6 +381,14 @@ ViewObjectWidget::set_default_cursor (lay::Cursor::cursor_shape cursor)
   }
 }
 
+void
+ViewObjectWidget::ensure_entered ()
+{
+  if (! m_mouse_inside) {
+    enterEvent (0);
+  }
+}
+
 void 
 ViewObjectWidget::begin_mouse_event (lay::Cursor::cursor_shape cursor)
 {
@@ -434,7 +460,7 @@ BEGIN_PROTECTED
   const DragDropDataBase *dd = get_drag_drop_data (event->mimeData ());
   if (dd) {
 
-    db::DPoint p = m_trans.inverted () * db::DPoint (event->pos ().x (), height () - 1 - event->pos ().y ());
+    db::DPoint p = pixel_to_um (event->pos ());
 
     bool done = drag_enter_event (p, dd);
     service_iterator svc = begin_services ();
@@ -479,7 +505,7 @@ BEGIN_PROTECTED
   const DragDropDataBase *dd = get_drag_drop_data (event->mimeData ());
   if (dd) {
 
-    db::DPoint p = m_trans.inverted () * db::DPoint (event->pos ().x (), height () - 1 - event->pos ().y ());
+    db::DPoint p = pixel_to_um (event->pos ());
 
     bool done = drag_move_event (p, dd);
     service_iterator svc = begin_services ();
@@ -503,7 +529,7 @@ BEGIN_PROTECTED
   const DragDropDataBase *dd = get_drag_drop_data (event->mimeData ());
   if (dd) {
 
-    db::DPoint p = m_trans.inverted () * db::DPoint (event->pos ().x (), height () - 1 - event->pos ().y ());
+    db::DPoint p = pixel_to_um (event->pos ());
 
     bool done = drop_event (p, dd);
     service_iterator svc = begin_services ();
@@ -523,6 +549,7 @@ void
 ViewObjectWidget::mouseMoveEvent (QMouseEvent *e)
 {
 BEGIN_PROTECTED  
+  ensure_entered ();
   m_mouse_pos = e->pos ();
   m_mouse_buttons = qt_to_buttons (e->buttons (), e->modifiers ());
   do_mouse_move ();
@@ -543,7 +570,7 @@ ViewObjectWidget::do_mouse_move ()
 
     bool done = false; 
     
-    db::DPoint p = m_trans.inverted () * db::DPoint (m_mouse_pressed.x (), height () - 1 - m_mouse_pressed.y ());
+    db::DPoint p = pixel_to_um (m_mouse_pressed);
 
     for (std::list<ViewService *>::iterator g = m_grabbed.begin (); !done && g != m_grabbed.end (); ) {
       std::list<ViewService *>::iterator gg = g;
@@ -578,7 +605,7 @@ ViewObjectWidget::do_mouse_move ()
 
     bool done = false; 
 
-    db::DPoint p = m_trans.inverted () * db::DPoint (m_mouse_pos.x (), height () - 1 - m_mouse_pos.y ());
+    db::DPoint p = pixel_to_um (m_mouse_pos);
 
     for (std::list<ViewService *>::iterator g = m_grabbed.begin (); !done && g != m_grabbed.end (); ) {
       std::list<ViewService *>::iterator gg = g;
@@ -614,6 +641,7 @@ void
 ViewObjectWidget::mouseDoubleClickEvent (QMouseEvent *e)
 {
 BEGIN_PROTECTED  
+  ensure_entered ();
   begin_mouse_event (lay::Cursor::none);
 
   setFocus ();
@@ -626,7 +654,7 @@ BEGIN_PROTECTED
 
   unsigned int buttons = qt_to_buttons (e->buttons (), e->modifiers ());
 
-  db::DPoint p = m_trans.inverted () * db::DPoint (e->pos ().x (), height () - 1 - e->pos ().y ());
+  db::DPoint p = pixel_to_um (e->pos ());
 
   for (std::list<ViewService *>::iterator g = m_grabbed.begin (); !done && g != m_grabbed.end (); ) {
     std::list<ViewService *>::iterator gg = g;
@@ -659,6 +687,8 @@ void
 ViewObjectWidget::enterEvent (QEvent * /*event*/)
 {
 BEGIN_PROTECTED  
+  m_mouse_inside = true;
+
   begin_mouse_event ();
 
   bool done = false; 
@@ -723,12 +753,15 @@ BEGIN_PROTECTED
 
   end_mouse_event ();
 END_PROTECTED
+
+  m_mouse_inside = false;
 }
 
 void 
 ViewObjectWidget::wheelEvent (QWheelEvent *e)
 {
 BEGIN_PROTECTED  
+  ensure_entered ();
   begin_mouse_event ();
 
   e->ignore ();
@@ -738,7 +771,7 @@ BEGIN_PROTECTED
   unsigned int buttons = qt_to_buttons (e->buttons (), e->modifiers ());
   bool horizonal = (e->orientation () == Qt::Horizontal);
 
-  db::DPoint p = m_trans.inverted () * db::DPoint (e->pos ().x (), height () - 1 - e->pos ().y ());
+  db::DPoint p = pixel_to_um (e->pos ());
 
   for (std::list<ViewService *>::iterator g = m_grabbed.begin (); !done && g != m_grabbed.end (); ) {
     std::list<ViewService *>::iterator gg = g;
@@ -770,6 +803,7 @@ END_PROTECTED
 void 
 ViewObjectWidget::mousePressEvent (QMouseEvent *e)
 {
+  ensure_entered ();
   setFocus ();
 
   m_mouse_pos = e->pos ();
@@ -784,12 +818,13 @@ void
 ViewObjectWidget::mouseReleaseEvent (QMouseEvent *e)
 {
 BEGIN_PROTECTED  
+  ensure_entered ();
   begin_mouse_event ();
 
   bool done = false; 
 
   m_mouse_pos = e->pos ();
-  db::DPoint p = m_trans.inverted () * db::DPoint (e->pos ().x (), height () - 1 - e->pos ().y ());
+  db::DPoint p = pixel_to_um (e->pos ());
 
   for (std::list<ViewService *>::iterator g = m_grabbed.begin (); !done && g != m_grabbed.end (); ) {
     std::list<ViewService *>::iterator gg = g;
@@ -838,6 +873,12 @@ END_PROTECTED
   m_mouse_pressed_state = false;
 }
 
+db::DPoint
+ViewObjectWidget::pixel_to_um (const QPoint &pt) const
+{
+  return m_trans.inverted () * db::DPoint (pt.x (), height () - 1 - pt.y ());
+}
+
 void
 ViewObjectWidget::mouse_event_trans (const db::DCplxTrans &trans)
 {
diff --git a/src/laybasic/laybasic/layViewObject.h b/src/laybasic/laybasic/layViewObject.h
index 816241d2b..c89fb65cd 100644
--- a/src/laybasic/laybasic/layViewObject.h
+++ b/src/laybasic/laybasic/layViewObject.h
@@ -130,8 +130,8 @@ public:
    *  @param layout the layout where the cell lives in 
    *  @param cell_index The index of the cell
    */
-  CellDragDropData (const db::Layout *layout, const db::Library *library, db::cell_index_type cell_or_pcell_index, bool is_pcell)
-    : mp_layout (layout), mp_library (library), m_cell_index (cell_or_pcell_index), m_is_pcell (is_pcell)
+  CellDragDropData (const db::Layout *layout, const db::Library *library, db::cell_index_type cell_or_pcell_index, bool is_pcell, const std::vector<tl::Variant> &pcell_params = std::vector<tl::Variant> ())
+    : mp_layout (layout), mp_library (library), m_cell_index (cell_or_pcell_index), m_is_pcell (is_pcell), m_pcell_params (pcell_params)
   {
     //  .. nothing yet ..
   }
@@ -152,6 +152,14 @@ public:
     return mp_library;
   }
 
+  /**
+   *  @brief PCell parameters
+   */
+  const std::vector<tl::Variant> &pcell_params () const
+  {
+    return m_pcell_params;
+  }
+
   /**
    *  @brief Gets the index of the cell
    */
@@ -185,6 +193,7 @@ private:
   const db::Library *mp_library;
   db::cell_index_type m_cell_index;
   bool m_is_pcell;
+  std::vector<tl::Variant> m_pcell_params;
 };
 
 /**
@@ -962,6 +971,35 @@ public:
     return m_view_objects_dismissed;
   }
 
+  /**
+   *  @brief Gets the current mouse position
+   */
+  QPoint mouse_position () const
+  {
+    return m_mouse_pos;
+  }
+
+  /**
+   *  @brief Gets the current mouse position in micrometer units
+   */
+  db::DPoint mouse_position_um () const
+  {
+    return pixel_to_um (m_mouse_pos);
+  }
+
+  /**
+   *  @brief Translates a screen coordinate in micrometer coordinates
+   */
+  db::DPoint pixel_to_um (const QPoint &pt) const;
+
+  /**
+   *  @brief Gets a flag indicating whether the mouse is inside the window
+   */
+  bool mouse_in_window () const
+  {
+    return m_mouse_inside;
+  }
+
 protected:
   /**
    *  @brief Qt focus event handler
@@ -1052,8 +1090,10 @@ private:
   bool m_mouse_pressed_state;
   unsigned int m_mouse_buttons;
   bool m_in_mouse_move;
+  bool m_mouse_inside;
   lay::Cursor::cursor_shape m_cursor, m_default_cursor;
 
+  void ensure_entered ();
   void do_mouse_move ();
   void begin_mouse_event (lay::Cursor::cursor_shape cursor = lay::Cursor::keep);
   void end_mouse_event ();
diff --git a/src/laybasic/laybasic/layWidgets.cc b/src/laybasic/laybasic/layWidgets.cc
index aee5a598f..6ea947b02 100644
--- a/src/laybasic/laybasic/layWidgets.cc
+++ b/src/laybasic/laybasic/layWidgets.cc
@@ -590,7 +590,7 @@ LibrarySelectionComboBox::set_technology_filter (const std::string &tech, bool e
 void 
 LibrarySelectionComboBox::update_list ()
 {
-  blockSignals (true);
+  bool wasBlocked = blockSignals (true);
 
   db::Library *lib = current_library ();
 
@@ -620,7 +620,7 @@ LibrarySelectionComboBox::update_list ()
 
   set_current_library (lib);
 
-  blockSignals (false);
+  blockSignals (wasBlocked);
 }
 
 LibrarySelectionComboBox::~LibrarySelectionComboBox ()
diff --git a/src/laybasic/laybasic/laybasic.pro b/src/laybasic/laybasic/laybasic.pro
index 2e3e2b4c3..5cf65cefe 100644
--- a/src/laybasic/laybasic/laybasic.pro
+++ b/src/laybasic/laybasic/laybasic.pro
@@ -31,6 +31,7 @@ FORMS = \
   LayoutViewConfigPage2a.ui \
   LayoutViewConfigPage2b.ui \
   LayoutViewConfigPage2c.ui \
+  LayoutViewConfigPage2d.ui \
   LayoutViewConfigPage3a.ui \
   LayoutViewConfigPage3b.ui \
   LayoutViewConfigPage3c.ui \
@@ -73,7 +74,8 @@ FORMS = \
     NetInfoDialog.ui \
     NetExportDialog.ui \
     SelectCellViewForm.ui \
-    LayoutStatistics.ui
+    LayoutStatistics.ui \
+    D25TechnologyComponentEditor.ui
 
 RESOURCES = \
     laybasicResources.qrc \
@@ -115,6 +117,10 @@ SOURCES = \
   layEditable.cc \
   layEditStipplesForm.cc \
   layEditStippleWidget.cc \
+  layEditorOptionsFrame.cc \
+  layEditorOptionsPage.cc \
+  layEditorOptionsPages.cc \
+  layEditorServiceBase.cc \
   layFileDialog.cc \
   layFinder.cc \
   layFixedFont.cc \
@@ -184,7 +190,9 @@ SOURCES = \
     layDispatcher.cc \
     laySelectCellViewForm.cc \
     layLayoutStatisticsForm.cc \
-    gsiDeclLayNetlistBrowserDialog.cc
+    gsiDeclLayNetlistBrowserDialog.cc \
+    layD25TechnologyComponent.cc \
+    layLayoutViewFunctions.cc
 
 HEADERS = \
   gtf.h \
@@ -215,6 +223,10 @@ HEADERS = \
   layEditable.h \
   layEditStipplesForm.h \
   layEditStippleWidget.h \
+  layEditorOptionsFrame.h \
+  layEditorOptionsPage.h \
+  layEditorOptionsPages.h \
+  layEditorServiceBase.h \
   layFileDialog.h \
   layFinder.h \
   layFixedFont.h \
@@ -285,7 +297,9 @@ HEADERS = \
     layGenericSyntaxHighlighter.h \
     layDispatcher.h \
     laySelectCellViewForm.h \
-    layLayoutStatisticsForm.h
+    layLayoutStatisticsForm.h \
+    layD25TechnologyComponent.h \
+    layLayoutViewFunctions.h 
 
 INCLUDEPATH += $$TL_INC $$GSI_INC $$DB_INC $$RDB_INC $$LYM_INC
 DEPENDPATH += $$TL_INC $$GSI_INC $$DB_INC $$RDB_INC $$LYM_INC
diff --git a/src/laybasic/laybasic/laybasicConfig.h b/src/laybasic/laybasic/laybasicConfig.h
index 71a5a2019..dc772dea0 100644
--- a/src/laybasic/laybasic/laybasicConfig.h
+++ b/src/laybasic/laybasic/laybasicConfig.h
@@ -75,6 +75,9 @@ static const std::string cfg_sel_line_style ("sel-line-style");
 static const std::string cfg_sel_transient_mode ("sel-transient-mode");
 static const std::string cfg_sel_inside_pcells_mode ("sel-inside-pcells-mode");
 
+static const std::string cfg_tracking_cursor_color ("tracking-cursor-color");
+static const std::string cfg_tracking_cursor_enabled ("tracking-cursor-enabled");
+
 static const std::string cfg_markers_visible ("markers-visible");
 
 static const std::string cfg_min_inst_label_size ("min-inst-label-size");
diff --git a/src/laybasic/laybasic/laybasicResources.qrc b/src/laybasic/laybasic/laybasicResources.qrc
index 86e08c975..f9243ccc4 100644
--- a/src/laybasic/laybasic/laybasicResources.qrc
+++ b/src/laybasic/laybasic/laybasicResources.qrc
@@ -45,5 +45,6 @@
         <file>images/icon_device_bjt_24.png</file>
         <file>images/icon_device_bjt_16.png</file>
         <file>syntax/ur_text.xml</file>
+        <file>syntax/d25_text.xml</file>
     </qresource>
 </RCC>
diff --git a/src/laybasic/laybasic/syntax/d25_text.xml b/src/laybasic/laybasic/syntax/d25_text.xml
new file mode 100644
index 000000000..5e0877b74
--- /dev/null
+++ b/src/laybasic/laybasic/syntax/d25_text.xml
@@ -0,0 +1,76 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<!DOCTYPE language SYSTEM "language.dtd">
+
+<language name="UserPropertiesTextFormat">
+
+	<highlighting>
+
+		<contexts>
+
+			<context name="Normal" attribute="Normal Text">
+
+				<DetectChar attribute="String" char="&quot;" context="Quoted String"/>
+				<DetectChar attribute="Comment" char="#" context="Comment"/>
+				<DetectChar attribute="Raw String" char="'" context="Apostrophed String"/>
+
+				<RegExpr attribute="Normal" String=":" context="After LD"/>
+
+				<RegExpr attribute="Dec" String="\-?[0-9]+" context="#stay"/>
+				<DetectChar attribute="Normal" char="*" context="#stay"/>
+				<DetectChar attribute="Normal" char="(" context="#stay"/>
+				<DetectChar attribute="Normal" char=")" context="#stay"/>
+				<DetectChar attribute="Normal" char="/" context="#stay"/>
+				<RegExpr attribute="Raw String" String="[_a-zA-Z]\w*" context="#stay"/>
+
+				<RegExpr attribute="Error" String="[^\s]" context="Error"/>
+
+			</context>
+
+			<context name="Comment" attribute="Comment" lineEndContext="Normal">
+      </context>
+
+			<context name="After LD" attribute="Normal" lineEndContext="Normal">
+				<DetectChar attribute="Comment" char="#" context="Comment"/>
+				<RegExpr attribute="Float" String="\-?[0-9]([0-9]|_[0-9])*(\.[0-9]([0-9]|_[0-9])*)?([eE]\-?[1-9]([0-9]|_[0-9])*(\.[0-9]*)?)?" context="#stay"/>
+				<DetectChar attribute="Normal" char="," context="#stay"/>
+				<DetectChar attribute="Normal" char="=" context="#stay"/>
+				<StringDetect attribute="Symbol" String="zstart" context="#stay"/>
+				<StringDetect attribute="Symbol" String="zstop" context="#stay"/>
+				<StringDetect attribute="Symbol" String="height" context="#stay"/>
+				<RegExpr attribute="Error" String="[^\s]" context="Error"/>
+      </context>
+
+			<context name="Error" attribute="Error" lineEndContext="Normal">
+      </context>
+
+			<context name="Quoted String" attribute="String" lineEndContext="Error">
+				<StringDetect attribute="String" String="\\" context="#stay"/>
+				<RegExpr attribute="String" String="\\\&quot;" context="#stay"/>
+				<DetectChar char="&quot;" attribute="String" context="Normal"/>
+			</context>
+
+			<context name="Apostrophed String" attribute="Raw String" lineEndContext="Error">
+				<StringDetect attribute="String" String="\\" context="#stay"/>
+				<RegExpr attribute="String" String="\\\'" context="#stay"/>
+				<DetectChar char="'" attribute="Raw String" context="Normal"/>
+			</context>
+
+    </contexts>
+
+		<itemDatas>
+			<itemData name="Normal Text" defStyleNum="dsNormal"/>
+
+			<itemData name="Comment" defStyleNum="dsComment"/>
+			<itemData name="Float" defStyleNum="dsFloat"/>
+			<itemData name="Dec" defStyleNum="dsDecVal"/>
+			<itemData name="Symbol" defStyleNum="dsKeyword"/>
+			<itemData name="String" defStyleNum="dsString"/>
+			<itemData name="Raw String" defStyleNum="dsString" color="#DD4A4A" selColor="#DD4A4A"/>
+
+			<!-- use these to mark errors and alerts things -->
+			<itemData name="Error" defStyleNum="dsAlert"/>
+
+		</itemDatas>
+
+	</highlighting>
+</language>
diff --git a/src/laybasic/unit_tests/laySnap.cc b/src/laybasic/unit_tests/laySnapTests.cc
similarity index 55%
rename from src/laybasic/unit_tests/laySnap.cc
rename to src/laybasic/unit_tests/laySnapTests.cc
index 39a177a1f..9b2c37d03 100644
--- a/src/laybasic/unit_tests/laySnap.cc
+++ b/src/laybasic/unit_tests/laySnapTests.cc
@@ -51,95 +51,101 @@ TEST(1)
 
   view.set_max_hier_levels (1);
 
-  std::pair<bool, db::DPoint> res;
+  lay::PointSnapToObjectResult res;
 
   //  not hit
   res = lay::obj_snap (&view, db::DPoint (1.505, 1.505), db::DVector (), 0.1);
-  EXPECT_EQ (res.first, false);
-  EXPECT_EQ (res.second.to_string (), "1.505,1.505");
+  EXPECT_EQ (res.object_snap, lay::PointSnapToObjectResult::NoObject);
+  EXPECT_EQ (res.snapped_point.to_string (), "1.505,1.505");
 
   res = lay::obj_snap (&view, db::DPoint (0.505, 0.505), db::DVector (), 0.1);
-  EXPECT_EQ (res.first, true);
-  EXPECT_EQ (res.second.to_string (), "0.5,0.5");
+  EXPECT_EQ (res.object_snap, lay::PointSnapToObjectResult::ObjectEdge);
+  EXPECT_EQ (res.snapped_point.to_string (), "0.5,0.5");
 
   res = lay::obj_snap (&view, db::DPoint (0.485, 0.505), db::DVector (0.01, 0.01), 0.1);
-  EXPECT_EQ (res.first, true);
-  EXPECT_EQ (res.second.to_string (), "0.49,0.51");
+  EXPECT_EQ (res.object_snap, lay::PointSnapToObjectResult::ObjectEdge);
+  EXPECT_EQ (res.snapped_point.to_string (), "0.49,0.51");
+  EXPECT_EQ (res.object_ref.to_string (), "(0,1;1,0)");
 
   res = lay::obj_snap (&view, db::DPoint (0.205, 0.215), db::DVector (0.01, 0.025), 0.1);
-  EXPECT_EQ (res.first, false);
-  EXPECT_EQ (res.second.to_string (), "0.21,0.225");
+  EXPECT_EQ (res.object_snap, lay::PointSnapToObjectResult::NoObject);
+  EXPECT_EQ (res.snapped_point.to_string (), "0.21,0.225");
 
   res = lay::obj_snap (&view, db::DPoint (0.505, 1.005), db::DVector (), 0.1);
-  EXPECT_EQ (res.first, false);
-  EXPECT_EQ (res.second.to_string (), "0.505,1.005");
+  EXPECT_EQ (res.object_snap, lay::PointSnapToObjectResult::NoObject);
+  EXPECT_EQ (res.snapped_point.to_string (), "0.505,1.005");
 
   res = lay::obj_snap (&view, db::DPoint (0.005, 1.005), db::DVector (), 0.1);
-  EXPECT_EQ (res.first, true);
-  EXPECT_EQ (res.second.to_string (), "0,1");
+  EXPECT_EQ (res.object_snap, lay::PointSnapToObjectResult::ObjectVertex);
+  EXPECT_EQ (res.snapped_point.to_string (), "0,1");
+
+  res = lay::obj_snap (&view, db::DPoint (0.0, 1.005), db::DVector (), 0.1);
+  EXPECT_EQ (res.object_snap, lay::PointSnapToObjectResult::ObjectVertex);
+  EXPECT_EQ (res.snapped_point.to_string (), "0,1");
 
   res = lay::obj_snap (&view, db::DPoint (1.000, 0.505), db::DPoint (0.505, 0.500), db::DVector (), lay::AC_Horizontal, 0.1);
-  EXPECT_EQ (res.first, true);
-  EXPECT_EQ (res.second.to_string (), "0.495,0.505");
+  EXPECT_EQ (res.object_snap, lay::PointSnapToObjectResult::ObjectEdge);
+  EXPECT_EQ (res.snapped_point.to_string (), "0.495,0.505");
 
   //  projected snapping
   res = lay::obj_snap (&view, db::DPoint (1.000, 0.505), db::DPoint (0.005, 1.005), db::DVector (), lay::AC_Horizontal, 0.1);
-  EXPECT_EQ (res.first, true);
-  EXPECT_EQ (res.second.to_string (), "0,0.505");
+  EXPECT_EQ (res.object_snap, lay::PointSnapToObjectResult::ObjectUnspecific);
+  EXPECT_EQ (res.snapped_point.to_string (), "0,0.505");
+  EXPECT_EQ (res.object_ref.to_string (), "(0,1;0,1)");
 
-  std::pair<bool, db::DEdge> res2;
+  lay::TwoPointSnapToObjectResult res2;
 
   res2 = lay::obj_snap2 (&view, db::DPoint (1.5, 1.5), db::DVector (), 0.005, 1.0);
-  EXPECT_EQ (res2.first, false);
-  EXPECT_EQ (res2.second.to_string (), "(0,0;0,0)");
+  EXPECT_EQ (res2.any, false);
+  EXPECT_EQ (db::DEdge (res2.first, res2.second).to_string (), "(0,0;0,0)");
 
   res2 = lay::obj_snap2 (&view, db::DPoint (0.205, 0.5), db::DVector (), 0.005, 1.0);
-  EXPECT_EQ (res2.first, true);
-  EXPECT_EQ (res2.second.to_string (), "(0.3525,0.6475;0,0.295)");
+  EXPECT_EQ (res2.any, true);
+  EXPECT_EQ (db::DEdge (res2.first, res2.second).to_string (), "(0.3525,0.6475;0,0.295)");
 
   res2 = lay::obj_snap2 (&view, db::DPoint (0.205, 0.5), db::DVector (), lay::AC_Horizontal, 0.005, 1.0);
-  EXPECT_EQ (res2.first, true);
-  EXPECT_EQ (res2.second.to_string (), "(0,0.5;0.5,0.5)");
+  EXPECT_EQ (res2.any, true);
+  EXPECT_EQ (db::DEdge (res2.first, res2.second).to_string (), "(0,0.5;0.5,0.5)");
 
   res2 = lay::obj_snap2 (&view, db::DPoint (0.205, 0.5), db::DVector (0.03, 0.03), lay::AC_Horizontal, 0.005, 1.0);
-  EXPECT_EQ (res2.first, true);
-  EXPECT_EQ (res2.second.to_string (), "(0,0.51;0.49,0.51)");
+  EXPECT_EQ (res2.any, true);
+  EXPECT_EQ (db::DEdge (res2.first, res2.second).to_string (), "(0,0.51;0.49,0.51)");
 
   res2 = lay::obj_snap2 (&view, db::DPoint (0.205, 0.5), db::DVector (), lay::AC_Vertical, 0.005, 1.0);
-  EXPECT_EQ (res2.first, true);
-  EXPECT_EQ (res2.second.to_string (), "(0.205,0.795;0.205,0)");
+  EXPECT_EQ (res2.any, true);
+  EXPECT_EQ (db::DEdge (res2.first, res2.second).to_string (), "(0.205,0.795;0.205,0)");
 
   res2 = lay::obj_snap2 (&view, db::DPoint (0.205, 0.5), db::DVector (), lay::AC_Diagonal, 0.005, 1.0);
-  EXPECT_EQ (res2.first, true);
-  EXPECT_EQ (res2.second.to_string (), "(0.3525,0.6475;0,0.295)");
+  EXPECT_EQ (res2.any, true);
+  EXPECT_EQ (db::DEdge (res2.first, res2.second).to_string (), "(0.3525,0.6475;0,0.295)");
 
   res2 = lay::obj_snap2 (&view, db::DPoint (0.205, 0.505), db::DVector (), lay::AC_Ortho, 0.005, 1.0);
-  EXPECT_EQ (res2.first, true);
-  EXPECT_EQ (res2.second.to_string (), "(0,0.505;0.495,0.505)");
+  EXPECT_EQ (res2.any, true);
+  EXPECT_EQ (db::DEdge (res2.first, res2.second).to_string (), "(0,0.505;0.495,0.505)");
 
   res2 = lay::obj_snap2 (&view, db::DPoint (0.205, 0.5), db::DVector (), lay::AC_Any, 0.005, 1.0);
-  EXPECT_EQ (res2.first, true);
-  EXPECT_EQ (res2.second.to_string (), "(0.3525,0.6475;0,0.295)");
+  EXPECT_EQ (res2.any, true);
+  EXPECT_EQ (db::DEdge (res2.first, res2.second).to_string (), "(0.3525,0.6475;0,0.295)");
 
   res2 = lay::obj_snap2 (&view, db::DPoint (0.205, 0.495), db::DVector (0.01, 0.01), 0.005, 1.0);
-  EXPECT_EQ (res2.first, true);
-  EXPECT_EQ (res2.second.to_string (), "(0.355,0.645;0,0.29)");
+  EXPECT_EQ (res2.any, true);
+  EXPECT_EQ (db::DEdge (res2.first, res2.second).to_string (), "(0.355,0.645;0,0.29)");
 
   res2 = lay::obj_snap2 (&view, db::DPoint (0.5, 0.5), db::DVector (), 0.005, 1.0);
-  EXPECT_EQ (res2.first, false);
-  EXPECT_EQ (res2.second.to_string (), "(0,0;0,0)");
+  EXPECT_EQ (res2.any, false);
+  EXPECT_EQ (db::DEdge (res2.first, res2.second).to_string (), "(0,0;0,0)");
 
   res2 = lay::obj_snap2 (&view, db::DPoint (0.005, 0.5), db::DVector (), 0.005, 1.0);
-  EXPECT_EQ (res2.first, true);
-  EXPECT_EQ (res2.second.to_string (), "(0,0.5;0.5,0.5)");
+  EXPECT_EQ (res2.any, true);
+  EXPECT_EQ (db::DEdge (res2.first, res2.second).to_string (), "(0,0.5;0.5,0.5)");
 
   res2 = lay::obj_snap2 (&view, db::DPoint (0.0, 0.5), db::DVector (), 0.005, 1.0);
-  EXPECT_EQ (res2.first, false);
-  EXPECT_EQ (res2.second.to_string (), "(0,0;0,0)");
+  EXPECT_EQ (res2.any, false);
+  EXPECT_EQ (db::DEdge (res2.first, res2.second).to_string (), "(0,0;0,0)");
 
   res2 = lay::obj_snap2 (&view, db::DPoint (-0.2, 0.5), db::DVector (), 0.005, 1.0);
-  EXPECT_EQ (res2.first, false);
-  EXPECT_EQ (res2.second.to_string (), "(0,0;0,0)");
+  EXPECT_EQ (res2.any, false);
+  EXPECT_EQ (db::DEdge (res2.first, res2.second).to_string (), "(0,0;0,0)");
 
 }
 
diff --git a/src/laybasic/unit_tests/unit_tests.pro b/src/laybasic/unit_tests/unit_tests.pro
index 0aeab4b3d..d948a1d87 100644
--- a/src/laybasic/unit_tests/unit_tests.pro
+++ b/src/laybasic/unit_tests/unit_tests.pro
@@ -13,10 +13,10 @@ SOURCES = \
   layLayerProperties.cc \
   layParsedLayerSource.cc \
   layRenderer.cc \
-  laySnap.cc \
   layNetlistBrowserModelTests.cc \
     layNetlistBrowserTreeModelTests.cc \
-    layAbstractMenuTests.cc
+    layAbstractMenuTests.cc \
+  laySnapTests.cc
 
 INCLUDEPATH += $$TL_INC $$LAYBASIC_INC $$DB_INC $$GSI_INC $$OUT_PWD/../laybasic
 DEPENDPATH += $$TL_INC $$LAYBASIC_INC $$DB_INC $$GSI_INC $$OUT_PWD/../laybasic
diff --git a/src/plugins/streamers/gds2/db_plugin/contrib/dbGDS2TextReader.cc b/src/plugins/streamers/gds2/db_plugin/contrib/dbGDS2TextReader.cc
index 028d801a9..ee363ed67 100644
--- a/src/plugins/streamers/gds2/db_plugin/contrib/dbGDS2TextReader.cc
+++ b/src/plugins/streamers/gds2/db_plugin/contrib/dbGDS2TextReader.cc
@@ -61,7 +61,7 @@ GDS2ReaderText::read (db::Layout &layout, const db::LoadLayoutOptions &options)
   db::GDS2ReaderOptions gds2_options = options.get_options<db::GDS2ReaderOptions> ();
   db::CommonReaderOptions common_options = options.get_options<db::CommonReaderOptions> ();
 
-  return basic_read (layout, common_options.layer_map, common_options.create_other_layers, common_options.enable_text_objects, common_options.enable_properties, false, gds2_options.box_mode);
+  return basic_read (layout, common_options.layer_map, common_options.create_other_layers, common_options.enable_text_objects, common_options.enable_properties, false, gds2_options.box_mode, common_options.cell_conflict_resolution);
 }
 
 const LayerMap &
@@ -259,7 +259,7 @@ GDS2ReaderText::get_double ()
 }
 
 void
-GDS2ReaderText::get_string (tl::string &s) const
+GDS2ReaderText::get_string (std::string &s) const
 {
   //  TODO: get rid of this const_cast hack
   s = (const_cast<GDS2ReaderText *> (this))->reader.skip ();
diff --git a/src/plugins/streamers/gds2/db_plugin/contrib/dbGDS2TextReader.h b/src/plugins/streamers/gds2/db_plugin/contrib/dbGDS2TextReader.h
index 4b394d13b..56de72863 100644
--- a/src/plugins/streamers/gds2/db_plugin/contrib/dbGDS2TextReader.h
+++ b/src/plugins/streamers/gds2/db_plugin/contrib/dbGDS2TextReader.h
@@ -112,7 +112,7 @@ private:
 
   virtual std::string path () const;
   const char *get_string ();
-  void get_string (tl::string &s) const;
+  void get_string (std::string &s) const;
   int get_int ();
   short get_short ();
   unsigned short get_ushort ();
diff --git a/src/plugins/streamers/gds2/db_plugin/dbGDS2Reader.cc b/src/plugins/streamers/gds2/db_plugin/dbGDS2Reader.cc
index f0fc9ac22..772da9429 100644
--- a/src/plugins/streamers/gds2/db_plugin/dbGDS2Reader.cc
+++ b/src/plugins/streamers/gds2/db_plugin/dbGDS2Reader.cc
@@ -64,7 +64,7 @@ GDS2Reader::read (db::Layout &layout, const db::LoadLayoutOptions &options)
   --m_recnum;
   m_reclen = 0;
 
-  return basic_read (layout, m_common_options.layer_map, m_common_options.create_other_layers, m_common_options.enable_text_objects, m_common_options.enable_properties, m_options.allow_multi_xy_records, m_options.box_mode);
+  return basic_read (layout, m_common_options.layer_map, m_common_options.create_other_layers, m_common_options.enable_text_objects, m_common_options.enable_properties, m_options.allow_multi_xy_records, m_options.box_mode, m_common_options.cell_conflict_resolution);
 }
 
 const LayerMap &
@@ -210,7 +210,7 @@ GDS2Reader::get_string ()
 }
 
 void
-GDS2Reader::get_string (tl::string &s) const
+GDS2Reader::get_string (std::string &s) const
 {
   s.assign ((const char *) mp_rec_buf, 0, m_reclen);
 }
diff --git a/src/plugins/streamers/gds2/db_plugin/dbGDS2Reader.h b/src/plugins/streamers/gds2/db_plugin/dbGDS2Reader.h
index e5bbb4aa3..2b51144dd 100644
--- a/src/plugins/streamers/gds2/db_plugin/dbGDS2Reader.h
+++ b/src/plugins/streamers/gds2/db_plugin/dbGDS2Reader.h
@@ -126,7 +126,7 @@ private:
 
   virtual std::string path () const;
   virtual const char *get_string ();
-  virtual void get_string (tl::string &s) const;
+  virtual void get_string (std::string &s) const;
   virtual int get_int ();
   virtual short get_short ();
   virtual unsigned short get_ushort ();
diff --git a/src/plugins/streamers/gds2/db_plugin/dbGDS2ReaderBase.cc b/src/plugins/streamers/gds2/db_plugin/dbGDS2ReaderBase.cc
index 1541960e0..d79793638 100644
--- a/src/plugins/streamers/gds2/db_plugin/dbGDS2ReaderBase.cc
+++ b/src/plugins/streamers/gds2/db_plugin/dbGDS2ReaderBase.cc
@@ -84,7 +84,7 @@ GDS2ReaderBase::~GDS2ReaderBase ()
 }
 
 const LayerMap &
-GDS2ReaderBase::basic_read (db::Layout &layout, const LayerMap &layer_map, bool create_other_layers, bool enable_text_objects, bool enable_properties, bool allow_multi_xy_records, unsigned int box_mode)
+GDS2ReaderBase::basic_read (db::Layout &layout, const LayerMap &layer_map, bool create_other_layers, bool enable_text_objects, bool enable_properties, bool allow_multi_xy_records, unsigned int box_mode, db::CommonReader::CellConflictResolution cc_resolution)
 {
   m_layer_map = layer_map;
   m_layer_map.prepare (layout);
@@ -95,9 +95,17 @@ GDS2ReaderBase::basic_read (db::Layout &layout, const LayerMap &layer_map, bool
   m_box_mode = box_mode;
   m_create_layers = create_other_layers;
 
+  set_cell_conflict_resolution (cc_resolution);
+
   layout.start_changes ();
-  do_read (layout);
-  layout.end_changes ();
+  try {
+    do_read (layout);
+    finish (layout);
+    layout.end_changes ();
+  } catch (...) {
+    layout.end_changes ();
+    throw;
+  }
 
   return m_layer_map;
 }
@@ -235,7 +243,6 @@ GDS2ReaderBase::do_read (db::Layout &layout)
 {
   m_cellname = "";
   m_libname = "";
-  m_mapped_cellnames.clear ();
 
   //  read header
   if (get_record () != sHEADER) {
@@ -349,7 +356,7 @@ GDS2ReaderBase::do_read (db::Layout &layout)
 
     } else {
 
-      db::cell_index_type cell_index = make_cell (layout, m_cellname.c_str (), false);
+      db::cell_index_type cell_index = make_cell (layout, m_cellname);
 
       db::Cell *cell = &layout.cell (cell_index);
 
@@ -359,8 +366,6 @@ GDS2ReaderBase::do_read (db::Layout &layout)
         if (layout.recover_proxy_as (cell_index, ctx->second.begin (), ctx->second.end (), &layer_mapping)) {
           //  ignore everything in that cell since it is created by the import:
           cell = 0;
-          //  marks the cell for begin addressed by REF's despite being a proxy:
-          m_mapped_cellnames.insert (std::make_pair (m_cellname, m_cellname));
         }
       }
       
@@ -973,54 +978,6 @@ GDS2ReaderBase::read_box (db::Layout &layout, db::Cell &cell)
   }
 }
 
-db::cell_index_type
-GDS2ReaderBase::make_cell (db::Layout &layout, const char *cn, bool for_instance)
-{
-  db::cell_index_type ci = 0;
-
-  //  map to the real name which maybe a different one due to localization
-  //  of proxy cells (they are not to be reopened)
-  bool is_mapped = false;
-  if (! m_mapped_cellnames.empty ()) {
-    std::map<tl::string, tl::string>::const_iterator n = m_mapped_cellnames.find (cn);
-    if (n != m_mapped_cellnames.end ()) {
-      cn = n->second.c_str ();
-      is_mapped = true;
-    }
-  }
-
-  std::pair<bool, db::cell_index_type> c = layout.cell_by_name (cn);
-  if (c.first && (is_mapped || ! layout.cell (c.second).is_proxy ())) {
-
-    //  cell already there: just add instance (cell might have been created through forward reference)
-    //  NOTE: we don't address "reopened" proxies as proxies are always local to a layout
-
-    ci = c.second;
-
-    //  mark the cell as read
-    if (! for_instance) {
-      layout.cell (ci).set_ghost_cell (false);
-    }
-
-  } else {
-
-    ci = layout.add_cell (cn);
-
-    if (for_instance) {
-      //  mark this cell a "ghost cell" until it's actually read
-      layout.cell (ci).set_ghost_cell (true);
-    }
-
-    if (c.first) {
-      //  this cell has been given a new name: remember this name for localization
-      m_mapped_cellnames.insert (std::make_pair (cn, layout.cell_name (ci)));
-    }
-
-  }
-
-  return ci;
-}
-
 void 
 GDS2ReaderBase::read_ref (db::Layout &layout, db::Cell & /*cell*/, bool array, tl::vector<db::CellInstArray> &instances, tl::vector<db::CellInstArrayWithProperties> &instances_with_props)
 {
@@ -1033,7 +990,7 @@ GDS2ReaderBase::read_ref (db::Layout &layout, db::Cell & /*cell*/, bool array, t
     error (tl::to_string (tr ("SNAME record expected")));
   }
 
-  db::cell_index_type ci = make_cell (layout, get_string (), true);
+  db::cell_index_type ci = cell_for_instance (layout, get_string ());
 
   bool mirror = false;
   int angle = 0;
diff --git a/src/plugins/streamers/gds2/db_plugin/dbGDS2ReaderBase.h b/src/plugins/streamers/gds2/db_plugin/dbGDS2ReaderBase.h
index 829ccea71..a094da9fb 100644
--- a/src/plugins/streamers/gds2/db_plugin/dbGDS2ReaderBase.h
+++ b/src/plugins/streamers/gds2/db_plugin/dbGDS2ReaderBase.h
@@ -29,6 +29,7 @@
 #include "dbLayout.h"
 #include "dbReader.h"
 #include "dbStreamLayers.h"
+#include "dbCommonReader.h"
 
 #include "tlException.h"
 #include "tlInternational.h"
@@ -49,7 +50,7 @@ struct GDS2XY
  *  @brief The GDS2 format basic stream reader
  */
 class DB_PLUGIN_PUBLIC GDS2ReaderBase
-  : public ReaderBase
+  : public CommonReader
 {
 public: 
   /**
@@ -86,20 +87,21 @@ protected:
    *  @param enable_properties A flag indicating whether to read user properties
    *  @param allow_multi_xy_records If true, tries to check for multiple XY records for BOUNDARY elements
    *  @param box_mode How to treat BOX records (0: ignore, 1: as rectangles, 2: as boundaries, 3: error)
+   *  @param cc_resolution The cell name conflict resolution mode
    *  @return The LayerMap object that tells where which layer was loaded
    */
-  const LayerMap &basic_read (db::Layout &layout, const LayerMap &layer_map, bool create_other_layers, bool enable_text_objects, bool enable_properties, bool allow_multi_xy_records, unsigned int box_mode);
+  const LayerMap &basic_read (db::Layout &layout, const LayerMap &layer_map, bool create_other_layers, bool enable_text_objects, bool enable_properties, bool allow_multi_xy_records, unsigned int box_mode, db::CommonReader::CellConflictResolution cc_resolution);
 
   /**
    *  @brief Accessor method to the current cellname
    */
-  const tl::string &cellname () const { return m_cellname; }
+  const std::string &cellname () const { return m_cellname; }
 
 private:
   friend class GDS2ReaderLayerMapping;
 
   LayerMap m_layer_map;
-  tl::string m_cellname;
+  std::string m_cellname;
   std::string m_libname;
   double m_dbu, m_dbuu;
   bool m_create_layers;
@@ -109,7 +111,6 @@ private:
   unsigned int m_box_mode;
   std::map <tl::string, std::vector<std::string> > m_context_info;
   std::vector <db::Point> m_all_points;
-  std::map <tl::string, tl::string> m_mapped_cellnames;
 
   void read_context_info_cell ();
   void read_boundary (db::Layout &layout, db::Cell &cell, bool from_box_record);
@@ -117,7 +118,6 @@ private:
   void read_text (db::Layout &layout, db::Cell &cell);
   void read_box (db::Layout &layout, db::Cell &cell);
   void read_ref (db::Layout &layout, db::Cell &cell, bool array, tl::vector<db::CellInstArray> &instances, tl::vector<db::CellInstArrayWithProperties> &insts_wp);
-  db::cell_index_type make_cell (db::Layout &layout, const char *cn, bool for_instance);
 
   void do_read (db::Layout &layout);
 
@@ -125,12 +125,15 @@ private:
   std::pair <bool, db::properties_id_type> finish_element (db::PropertiesRepository &rep);
   void finish_element ();
 
+  virtual void common_reader_error (const std::string &msg) { error (msg); }
+  virtual void common_reader_warn (const std::string &msg) { warn (msg); }
+
   virtual void error (const std::string &txt) = 0;
   virtual void warn (const std::string &txt) = 0;
 
   virtual std::string path () const = 0;
   virtual const char *get_string () = 0;
-  virtual void get_string (tl::string &s) const = 0;
+  virtual void get_string (std::string &s) const = 0;
   virtual int get_int () = 0;
   virtual short get_short () = 0;
   virtual unsigned short get_ushort () = 0;
diff --git a/src/plugins/streamers/gds2/unit_tests/dbGDS2Reader.cc b/src/plugins/streamers/gds2/unit_tests/dbGDS2Reader.cc
index b1971b0e4..838260bf3 100644
--- a/src/plugins/streamers/gds2/unit_tests/dbGDS2Reader.cc
+++ b/src/plugins/streamers/gds2/unit_tests/dbGDS2Reader.cc
@@ -366,6 +366,8 @@ TEST(Bug_121_1)
     reader.read (layout);
   }
 
+  fflush(stdout);
+
   std::string fn_au (tl::testsrc () + "/testdata/gds/bug_121_au1.gds");
   db::compare_layouts (_this, layout, fn_au, db::WriteGDS2, 1);
 }
@@ -434,3 +436,100 @@ TEST(3_AdvancedMapping)
   std::string fn_au (tl::testsrc () + "/testdata/gds/alm_au.gds");
   db::compare_layouts (_this, layout, fn_au, db::WriteGDS2, 1);
 }
+
+TEST(4_CollectModeRename)
+{
+  db::Manager m (false);
+  db::Layout layout (&m);
+
+  db::LoadLayoutOptions options;
+  options.get_options<db::CommonReaderOptions> ().cell_conflict_resolution = db::CommonReader::RenameCell;
+
+  {
+    tl::InputStream file (tl::testsrc () + "/testdata/gds/collect_basic.gds");
+    db::Reader reader (file);
+    reader.read (layout, options);
+  }
+
+  {
+    tl::InputStream file (tl::testsrc () + "/testdata/gds/collect_added.gds");
+    db::Reader reader (file);
+    reader.read (layout, options);
+  }
+
+  std::string fn_au (tl::testsrc () + "/testdata/gds/collect_rename_au.gds");
+  db::compare_layouts (_this, layout, fn_au, db::WriteGDS2, 1);
+}
+
+TEST(4_CollectModeOverwrite)
+{
+  db::Manager m (false);
+  db::Layout layout (&m);
+
+  db::LoadLayoutOptions options;
+  options.get_options<db::CommonReaderOptions> ().cell_conflict_resolution = db::CommonReader::OverwriteCell;
+
+  {
+    tl::InputStream file (tl::testsrc () + "/testdata/gds/collect_basic.gds");
+    db::Reader reader (file);
+    reader.read (layout, options);
+  }
+
+  {
+    tl::InputStream file (tl::testsrc () + "/testdata/gds/collect_added.gds");
+    db::Reader reader (file);
+    reader.read (layout, options);
+  }
+
+  std::string fn_au (tl::testsrc () + "/testdata/gds/collect_overwrite_au.gds");
+  db::compare_layouts (_this, layout, fn_au, db::WriteGDS2, 1);
+}
+
+TEST(4_CollectModeSkip)
+{
+  db::Manager m (false);
+  db::Layout layout (&m);
+
+  db::LoadLayoutOptions options;
+  options.get_options<db::CommonReaderOptions> ().cell_conflict_resolution = db::CommonReader::SkipNewCell;
+
+  {
+    tl::InputStream file (tl::testsrc () + "/testdata/gds/collect_basic.gds");
+    db::Reader reader (file);
+    reader.read (layout, options);
+  }
+
+  {
+    tl::InputStream file (tl::testsrc () + "/testdata/gds/collect_added.gds");
+    db::Reader reader (file);
+    reader.read (layout, options);
+  }
+
+  std::string fn_au (tl::testsrc () + "/testdata/gds/collect_skip_au.gds");
+  db::compare_layouts (_this, layout, fn_au, db::WriteGDS2, 1);
+}
+
+TEST(4_CollectModeAdd)
+{
+  db::Manager m (false);
+  db::Layout layout (&m);
+
+  db::LoadLayoutOptions options;
+  options.get_options<db::CommonReaderOptions> ().cell_conflict_resolution = db::CommonReader::AddToCell;
+
+  {
+    tl::InputStream file (tl::testsrc () + "/testdata/gds/collect_basic.gds");
+    db::Reader reader (file);
+    reader.read (layout, options);
+  }
+
+  {
+    tl::InputStream file (tl::testsrc () + "/testdata/gds/collect_added.gds");
+    db::Reader reader (file);
+    reader.read (layout, options);
+  }
+
+  std::string fn_au (tl::testsrc () + "/testdata/gds/collect_add_au.gds");
+  db::compare_layouts (_this, layout, fn_au, db::WriteGDS2, 1);
+}
+
diff --git a/src/plugins/streamers/lefdef/lay_plugin/layLEFDEFImportDialogs.cc b/src/plugins/streamers/lefdef/lay_plugin/layLEFDEFImportDialogs.cc
index 1b0e6d2c2..765640e43 100644
--- a/src/plugins/streamers/lefdef/lay_plugin/layLEFDEFImportDialogs.cc
+++ b/src/plugins/streamers/lefdef/lay_plugin/layLEFDEFImportDialogs.cc
@@ -340,26 +340,6 @@ END_PROTECTED
 // -----------------------------------------------------------------------------------------------
 //  LEFDEF technology components editor
 
-static void
-indicate_error (QWidget *le, const tl::Exception *ex)
-{
-  //  by the way, update the foreground color of the cell edit box as well (red, if not valid)
-  QPalette pl = le->palette ();
-  if (ex) {
-    pl.setColor (QPalette::Active, QPalette::Text, Qt::red);
-    pl.setColor (QPalette::Active, QPalette::Base, QColor (Qt::red).lighter (180));
-    le->setToolTip (tl::to_qstring (ex->msg ()));
-  } else {
-    QWidget *pw = dynamic_cast<QWidget *> (le->parent ());
-    tl_assert (pw != 0);
-    pl.setColor (QPalette::Active, QPalette::Text, pw->palette ().color (QPalette::Text));
-    pl.setColor (QPalette::Active, QPalette::Base, pw->palette ().color (QPalette::Base));
-    le->setToolTip (QString ());
-  }
-  le->setPalette (pl);
-}
-
-
 LEFDEFReaderOptionsEditor::LEFDEFReaderOptionsEditor (QWidget *parent)
   : lay::StreamReaderOptionsPage (parent), mp_tech (0)
 {
diff --git a/src/plugins/streamers/oasis/db_plugin/dbOASISReader.cc b/src/plugins/streamers/oasis/db_plugin/dbOASISReader.cc
index d7b4fd67d..3bf5485a5 100644
--- a/src/plugins/streamers/oasis/db_plugin/dbOASISReader.cc
+++ b/src/plugins/streamers/oasis/db_plugin/dbOASISReader.cc
@@ -144,9 +144,12 @@ OASISReader::read (db::Layout &layout, const db::LoadLayoutOptions &options)
   m_read_all_properties = oasis_options.read_all_properties;
   m_expect_strict_mode = oasis_options.expect_strict_mode;
 
+  set_cell_conflict_resolution (common_options.cell_conflict_resolution);
+
   layout.start_changes ();
   try {
     do_read (layout);
+    finish (layout);
     layout.end_changes ();
   } catch (...) {
     layout.end_changes ();
@@ -758,17 +761,11 @@ OASISReader::do_read (db::Layout &layout)
   id_mode propstring_id_mode = any;
   id_mode propname_id_mode = any;
 
-  m_cellnames.clear ();
   m_cellname_properties.clear ();
   m_textstrings.clear ();
   m_propstrings.clear ();
   m_propnames.clear ();
   m_layernames.clear ();
-  m_cells_by_id.clear ();
-  m_cells_by_name.clear ();
-  m_defined_cells_by_id.clear ();
-  m_defined_cells_by_name.clear ();
-  m_mapped_cellnames.clear ();
 
   m_instances.clear ();
   m_instances_with_props.clear ();
@@ -826,9 +823,7 @@ OASISReader::do_read (db::Layout &layout)
         get (id);
       }
 
-      if (! m_cellnames.insert (std::make_pair (id, name)).second) {
-        error (tl::sprintf (tl::to_string (tr ("A CELLNAME with id %ld is present already")), id));
-      }
+      rename_cell (layout, id, name);
 
       reset_modal_variables ();
 
@@ -1150,36 +1145,17 @@ OASISReader::do_read (db::Layout &layout)
 
         unsigned long id = 0;
         get (id);
-        if (! m_defined_cells_by_id.insert (id).second) {
+
+        std::pair<bool, db::cell_index_type> cc = cell_by_id (id);
+        if (cc.first && ! layout.cell (cc.second).is_ghost_cell ()) {
           error (tl::sprintf (tl::to_string (tr ("A cell with id %ld is defined already")), id));
         }
 
-        std::map <unsigned long, db::cell_index_type>::const_iterator c = m_cells_by_id.find (id);
-        if (c != m_cells_by_id.end ()) {
-
-          cell_index = c->second;
-          layout.cell (cell_index).set_ghost_cell (false);
-
-        } else {
-
-          std::map <unsigned long, std::string>::const_iterator name = m_cellnames.find (id);
-          if (name == m_cellnames.end ()) {
-
-            cell_index = layout.add_cell ();
-            //  force a cell rename to empty to avoid name clashes of the generated
-            //  $x names with the same inside the OASIS file.
-            layout.rename_cell (cell_index, "");
-            m_forward_references.insert (std::make_pair (id, cell_index));
-
-          } else {
-
-            cell_index = make_cell (layout, name->second.c_str (), false);
-            m_cells_by_name.insert (std::make_pair (name->second, cell_index));
-
-          }
-
-          m_cells_by_id.insert (std::make_pair (id, cell_index));
+        cell_index = make_cell (layout, id);
 
+        m_cellname = name_for_id (id);
+        if (m_cellname.empty ()) {
+          m_cellname = std::string ("#") + tl::to_string (id);
         }
 
       } else {
@@ -1189,22 +1165,15 @@ OASISReader::do_read (db::Layout &layout)
         }
 
         std::string name = get_str ();
-        if (! m_defined_cells_by_name.insert (name).second) {
+
+        std::pair<bool, db::cell_index_type> cc = cell_by_name (name);
+        if (cc.first && ! layout.cell (cc.second).is_ghost_cell ()) {
           error (tl::sprintf (tl::to_string (tr ("A cell with name %s is defined already")), name.c_str ()));
         }
 
-        std::map <std::string, db::cell_index_type>::const_iterator c = m_cells_by_name.find (name);
-        if (c != m_cells_by_name.end ()) {
+        cell_index = make_cell (layout, name);
 
-          cell_index = c->second;
-          layout.cell (cell_index).set_ghost_cell (false);
-
-        } else {
-
-          cell_index = make_cell (layout, name.c_str (), false);
-          m_cells_by_name.insert (std::make_pair (name, cell_index));
-
-        }
+        m_cellname = name;
 
       }
 
@@ -1326,72 +1295,16 @@ OASISReader::do_read (db::Layout &layout)
 
   }
 
-  for (std::map <unsigned long, db::cell_index_type>::const_iterator fw = m_forward_references.begin (); fw != m_forward_references.end (); ++fw) {
-
-    std::map <unsigned long, std::string>::const_iterator cn = m_cellnames.find (fw->first);
-    if (cn == m_cellnames.end ()) {
-
-      error (tl::sprintf (tl::to_string (tr ("No cellname defined for cell name id %ld")), fw->first));
-
-    } else {
-
-      std::pair<bool, db::cell_index_type> c = layout.cell_by_name (cn->second.c_str ()); 
-      if (c.first) {
-
-        //  needed, since we have disabled updates
-        layout.force_update ();
-
-        //  add-on reading of forward-referenced cell: need to copy the new cell to the original one plus 
-        //  change instances of the new cell and delete the new cell then.
-
-        const db::Cell &new_cell = layout.cell (fw->second);
-        db::Cell &org_cell = layout.cell (c.second);
-
-        //  copy over the instances
-        for (db::Cell::const_iterator i = new_cell.begin (); ! i.at_end (); ++i) {
-          org_cell.insert (*i);
-        }
-
-        //  copy over the shapes
-        for (unsigned int l = 0; l < layout.layers (); ++l) {
-          if (layout.is_valid_layer (l) && ! new_cell.shapes (l).empty ()) {
-            org_cell.shapes (l).insert (new_cell.shapes (l));
-          }
-        }
-
-        //  replace all instances of the new cell with the original one
-        std::vector<std::pair<db::cell_index_type, db::Instance> > parents;
-        for (db::Cell::parent_inst_iterator pi = new_cell.begin_parent_insts (); ! pi.at_end (); ++pi) {
-          parents.push_back (std::make_pair (pi->parent_cell_index (), pi->child_inst ()));
-        }
-
-        for (std::vector<std::pair<db::cell_index_type, db::Instance> >::const_iterator p = parents.begin (); p != parents.end (); ++p) {
-          db::CellInstArray ia = p->second.cell_inst ();
-          ia.object ().cell_index (org_cell.cell_index ());
-          layout.cell (p->first).replace (p->second, ia);
-        }
-
-        //  finally delete the new cell
-        layout.delete_cell (new_cell.cell_index ());
-
-      } else {
-        layout.rename_cell (fw->second, cn->second.c_str ());
-      }
-
-    }
-
-  }
-
   //  attach the properties found in CELLNAME to the cells (which may have other properties)
   for (std::map<unsigned long, db::properties_id_type>::const_iterator p = m_cellname_properties.begin (); p != m_cellname_properties.end (); ++p) {
 
-    std::map <unsigned long, db::cell_index_type>::const_iterator c = m_cells_by_id.find (p->first);
-    if (c != m_cells_by_id.end ()) {
+    std::pair<bool, db::cell_index_type> c = cell_by_id (p->first);
+    if (c.first) {
 
       db::PropertiesRepository::properties_set cnp = layout.properties_repository ().properties (p->second);
 
       //  Merge existing properties with the ones from CELLNAME
-      db::Cell &cell = layout.cell (c->second);
+      db::Cell &cell = layout.cell (c.second);
       if (cell.prop_id () != 0) {
         db::PropertiesRepository::properties_set cp = layout.properties_repository ().properties (cell.prop_id ());
         cnp.insert (cp.begin (), cp.end ());
@@ -1844,54 +1757,6 @@ OASISReader::read_repetition ()
   return mm_repetition.get ().size () > 1;
 }
 
-db::cell_index_type
-OASISReader::make_cell (db::Layout &layout, const char *cn, bool for_instance)
-{
-  db::cell_index_type ci = 0;
-
-  //  map to the real name which maybe a different one due to localization
-  //  of proxy cells (they are not to be reopened)
-  bool is_mapped = false;
-  if (! m_mapped_cellnames.empty ()) {
-    std::map<tl::string, tl::string>::const_iterator n = m_mapped_cellnames.find (cn);
-    if (n != m_mapped_cellnames.end ()) {
-      cn = n->second.c_str ();
-      is_mapped = true;
-    }
-  }
-
-  std::pair<bool, db::cell_index_type> c = layout.cell_by_name (cn);
-  if (c.first && (is_mapped || ! layout.cell (c.second).is_proxy ())) {
-
-    //  cell already there: just add instance (cell might have been created through forward reference)
-    //  NOTE: we don't address "reopened" proxies as proxies are always local to a layout
-
-    ci = c.second;
-
-    //  mark the cell as read
-    if (! for_instance) {
-      layout.cell (ci).set_ghost_cell (false);
-    }
-
-  } else {
-
-    ci = layout.add_cell (cn);
-
-    if (for_instance) {
-      //  mark this cell a "ghost cell" until it's actually read
-      layout.cell (ci).set_ghost_cell (true);
-    }
-
-    if (c.first) {
-      //  this cell has been given a new name: remember this name for localization
-      m_mapped_cellnames.insert (std::make_pair (cn, layout.cell_name (ci)));
-    }
-
-  }
-
-  return ci;
-}
-
 void 
 OASISReader::do_read_placement (unsigned char r,
                                 bool xy_absolute,
@@ -1909,31 +1774,8 @@ OASISReader::do_read_placement (unsigned char r,
       //  cell by id
       unsigned long id;
       get (id);
-      std::map <unsigned long, db::cell_index_type>::const_iterator cid = m_cells_by_id.find (id);
-      if (cid == m_cells_by_id.end ()) {
 
-        //  create the cell
-        std::map <unsigned long, std::string>::const_iterator name = m_cellnames.find (id);
-        if (name == m_cellnames.end ()) {
-
-          mm_placement_cell = layout.add_cell ();
-          m_forward_references.insert (std::make_pair (id, mm_placement_cell.get ()));
-
-          //  temporarily mark as "ghost cell"
-          layout.cell (mm_placement_cell.get ()).set_ghost_cell (true);
-
-        } else {
-
-          mm_placement_cell = make_cell (layout, name->second.c_str (), true);
-          m_cells_by_name.insert (std::make_pair (name->second, mm_placement_cell.get ()));
-         
-        }
-
-        m_cells_by_id.insert (std::make_pair (id, mm_placement_cell.get ()));
-
-      } else {
-        mm_placement_cell = cid->second;
-      }
+      mm_placement_cell = cell_for_instance (layout, id);
 
     } else {
 
@@ -1941,15 +1783,7 @@ OASISReader::do_read_placement (unsigned char r,
       std::string name;
       get_str (name);
 
-      std::map <std::string, db::cell_index_type>::const_iterator cid = m_cells_by_name.find (name);
-      if (cid == m_cells_by_name.end ()) {
-
-        mm_placement_cell = make_cell (layout, name.c_str (), true);
-        m_cells_by_name.insert (std::make_pair (name, mm_placement_cell.get ()));
-
-      } else {
-        mm_placement_cell = cid->second;
-      }
+      mm_placement_cell = cell_for_instance (layout, name);
 
     }
 
@@ -3433,7 +3267,6 @@ OASISReader::do_read_cell (db::cell_index_type cell_index, db::Layout &layout)
   m_instances_with_props.clear ();
 
   m_progress.set (m_stream.pos ());
-  m_cellname = layout.cell_name (cell_index);
 
   bool xy_absolute = true;
 
diff --git a/src/plugins/streamers/oasis/db_plugin/dbOASISReader.h b/src/plugins/streamers/oasis/db_plugin/dbOASISReader.h
index 63315e78a..a8a56e173 100644
--- a/src/plugins/streamers/oasis/db_plugin/dbOASISReader.h
+++ b/src/plugins/streamers/oasis/db_plugin/dbOASISReader.h
@@ -33,6 +33,7 @@
 #include "dbOASISFormat.h"
 #include "dbStreamLayers.h"
 #include "dbPropertiesRepository.h"
+#include "dbCommonReader.h"
 
 #include "tlException.h"
 #include "tlInternational.h"
@@ -62,7 +63,7 @@ public:
  *  @brief The OASIS format stream reader
  */
 class DB_PLUGIN_PUBLIC OASISReader
-  : public ReaderBase, 
+  : public CommonReader,
     public OASISDiagnostics
 {
 public: 
@@ -118,6 +119,7 @@ public:
    */
   virtual const char *format () const { return "OASIS"; }
 
+protected:
   /**
    *  @brief Issue an error with positional information
    *
@@ -132,6 +134,9 @@ public:
    */
   virtual void warn (const std::string &txt);
 
+  virtual void common_reader_error (const std::string &msg) { error (msg); }
+  virtual void common_reader_warn (const std::string &msg) { warn (msg); }
+
 private:
   friend class OASISReaderLayerMapping;
 
@@ -194,7 +199,6 @@ private:
   modal_variable<bool> mm_last_property_is_sprop;
   modal_variable<property_value_list> mm_last_value_list;
 
-  std::map <unsigned long, std::string> m_cellnames;
   std::map <unsigned long, db::properties_id_type> m_cellname_properties;
   std::map <unsigned long, std::string> m_textstrings;
   std::map <unsigned long, const db::StringRef *> m_text_forward_references;
@@ -205,18 +209,11 @@ private:
   tl::vector<db::CellInstArray> m_instances;
   tl::vector<db::CellInstArrayWithProperties> m_instances_with_props;
 
-  std::map <unsigned long, db::cell_index_type> m_cells_by_id;
-  std::map <unsigned long, db::cell_index_type> m_forward_references;
-  std::map <std::string, db::cell_index_type> m_cells_by_name;
   bool m_create_layers;
   bool m_read_texts;
   bool m_read_properties;
   bool m_read_all_properties;
 
-  std::set <unsigned long> m_defined_cells_by_id;
-  std::set <std::string> m_defined_cells_by_name;
-  std::map <tl::string, tl::string> m_mapped_cellnames;
-
   std::map <unsigned long, db::property_names_id_type> m_propname_forward_references;
   std::map <unsigned long, std::string> m_propvalue_forward_references;
   db::property_names_id_type m_s_gds_property_name_id;
@@ -238,7 +235,6 @@ private:
   void do_read_trapezoid (unsigned char r, bool xy_absolute,db::cell_index_type cell_index, db::Layout &layout);
   void do_read_ctrapezoid (bool xy_absolute,db::cell_index_type cell_index, db::Layout &layout);
   void do_read_circle (bool xy_absolute,db::cell_index_type cell_index, db::Layout &layout);
-  db::cell_index_type make_cell (db::Layout &layout, const char *cn, bool for_instance);
 
   void reset_modal_variables ();
 
diff --git a/src/plugins/streamers/oasis/db_plugin/dbOASISWriter.cc b/src/plugins/streamers/oasis/db_plugin/dbOASISWriter.cc
index a3e5b8c21..667c80b80 100644
--- a/src/plugins/streamers/oasis/db_plugin/dbOASISWriter.cc
+++ b/src/plugins/streamers/oasis/db_plugin/dbOASISWriter.cc
@@ -1150,6 +1150,18 @@ OASISWriter::reset_modal_variables ()
   mm_last_value_list.reset ();
 }
 
+static bool must_write_cell (const db::Cell &cref)
+{
+  //  Don't write proxy cells which are not employed
+  return ! cref.is_proxy () || ! cref.is_top ();
+}
+
+static bool skip_cell_body (const db::Cell &cref)
+{
+  //  Skip cell bodies for ghost cells unless empty (they are not longer ghost cells in this case)
+  return cref.is_ghost_cell () && cref.empty ();
+}
+
 void 
 OASISWriter::write (db::Layout &layout, tl::OutputStream &stream, const db::SaveLayoutOptions &options)
 {
@@ -1184,13 +1196,13 @@ OASISWriter::write (db::Layout &layout, tl::OutputStream &stream, const db::Save
   cells_by_index.reserve (cell_set.size ());
 
   for (db::Layout::bottom_up_const_iterator cell = layout.begin_bottom_up (); cell != layout.end_bottom_up (); ++cell) {
-    if (cell_set.find (*cell) != cell_set.end ()) {
+    if (cell_set.find (*cell) != cell_set.end () && must_write_cell (layout.cell (*cell))) {
       cells.push_back (*cell);
     }
   }
 
   for (db::Layout::const_iterator cell = layout.begin (); cell != layout.end (); ++cell) {
-    if (cell_set.find (cell->cell_index ()) != cell_set.end ()) {
+    if (cell_set.find (cell->cell_index ()) != cell_set.end () && must_write_cell (layout.cell (cell->cell_index ()))) {
       cells_by_index.push_back (cell->cell_index ());
     }
   }
@@ -1594,80 +1606,79 @@ OASISWriter::write (db::Layout &layout, tl::OutputStream &stream, const db::Save
     const db::Cell &cref (layout.cell (*cell));
     mp_cell = &cref;
 
-    //  don't write ghost cells unless they are not empty (any more)
-    //  also don't write proxy cells which are not employed
-    if ((! cref.is_ghost_cell () || ! cref.empty ()) && (! cref.is_proxy () || ! cref.is_top ())) {
+    //  skip cell body if the cell is not to be written
+    if (skip_cell_body (cref)) {
+      continue;
+    }
 
-      //  cell header 
+    //  cell header
 
-      cell_positions.insert (std::make_pair (*cell, mp_stream->pos ()));
+    cell_positions.insert (std::make_pair (*cell, mp_stream->pos ()));
 
-      write_record_id (13);  // CELL
-      write ((unsigned long) *cell);
+    write_record_id (13);  // CELL
+    write ((unsigned long) *cell);
 
-      reset_modal_variables ();
+    reset_modal_variables ();
 
-      if (m_options.write_cblocks) {
-        begin_cblock ();
-      }
+    if (m_options.write_cblocks) {
+      begin_cblock ();
+    }
 
-      //  context information as property named KLAYOUT_CONTEXT
-      if (cref.is_proxy () && options.write_context_info ()) {
+    //  context information as property named KLAYOUT_CONTEXT
+    if (cref.is_proxy () && options.write_context_info ()) {
 
-        context_prop_strings.clear ();
+      context_prop_strings.clear ();
 
-        if (layout.get_context_info (*cell, context_prop_strings)) {
+      if (layout.get_context_info (*cell, context_prop_strings)) {
 
-          write_record_id (28);
-          write_byte (char (0xf6)); 
-          std::map <std::string, unsigned long>::const_iterator pni = m_propnames.find (klayout_context_name);
-          tl_assert (pni != m_propnames.end ());
-          write (pni->second);
+        write_record_id (28);
+        write_byte (char (0xf6));
+        std::map <std::string, unsigned long>::const_iterator pni = m_propnames.find (klayout_context_name);
+        tl_assert (pni != m_propnames.end ());
+        write (pni->second);
 
-          write ((unsigned long) context_prop_strings.size ());
-
-          for (std::vector <std::string>::const_iterator c = context_prop_strings.begin (); c != context_prop_strings.end (); ++c) {
-            write_byte (14); // b-string by reference number
-            std::map <std::string, unsigned long>::const_iterator psi = m_propstrings.find (*c);
-            tl_assert (psi != m_propstrings.end ());
-            write (psi->second);
-          }
-
-          mm_last_property_name = klayout_context_name;
-          mm_last_property_is_sprop = false;
-          mm_last_value_list.reset ();
+        write ((unsigned long) context_prop_strings.size ());
 
+        for (std::vector <std::string>::const_iterator c = context_prop_strings.begin (); c != context_prop_strings.end (); ++c) {
+          write_byte (14); // b-string by reference number
+          std::map <std::string, unsigned long>::const_iterator psi = m_propstrings.find (*c);
+          tl_assert (psi != m_propstrings.end ());
+          write (psi->second);
         }
 
+        mm_last_property_name = klayout_context_name;
+        mm_last_property_is_sprop = false;
+        mm_last_value_list.reset ();
+
       }
 
-      if (cref.prop_id () != 0) {
-        write_props (cref.prop_id ());
-      }
-
-      //  instances
-      if (cref.cell_instances () > 0) {
-        write_insts (cell_set);
-      }
-
-      //  shapes
-      for (std::vector <std::pair <unsigned int, db::LayerProperties> >::const_iterator l = layers.begin (); l != layers.end (); ++l) {
-        const db::Shapes &shapes = cref.shapes (l->first);
-        if (! shapes.empty ()) {
-          write_shapes (l->second, shapes);
-          m_progress.set (mp_stream->pos ());
-        }
-      }
-
-      //  end CBLOCK if required
-      if (m_options.write_cblocks) {
-        end_cblock ();
-      } 
-
-      //  end of cell
-
     }
 
+    if (cref.prop_id () != 0) {
+      write_props (cref.prop_id ());
+    }
+
+    //  instances
+    if (cref.cell_instances () > 0) {
+      write_insts (cell_set);
+    }
+
+    //  shapes
+    for (std::vector <std::pair <unsigned int, db::LayerProperties> >::const_iterator l = layers.begin (); l != layers.end (); ++l) {
+      const db::Shapes &shapes = cref.shapes (l->first);
+      if (! shapes.empty ()) {
+        write_shapes (l->second, shapes);
+        m_progress.set (mp_stream->pos ());
+      }
+    }
+
+    //  end CBLOCK if required
+    if (m_options.write_cblocks) {
+      end_cblock ();
+    }
+
+    //  end of cell
+
   }
 
   //  write cell table at the end in strict mode (in that mode we need the cell positions
diff --git a/src/plugins/streamers/oasis/unit_tests/dbOASISWriter.cc b/src/plugins/streamers/oasis/unit_tests/dbOASISWriter.cc
index ce4f6c479..9e7e48aef 100644
--- a/src/plugins/streamers/oasis/unit_tests/dbOASISWriter.cc
+++ b/src/plugins/streamers/oasis/unit_tests/dbOASISWriter.cc
@@ -570,11 +570,11 @@ TEST(100)
 
   const char *expected = 
     "begin_lib 0.001\n"
+    "begin_cell {$4}\n"
+    "end_cell\n"
     "begin_cell {$1}\n"
     "box 1 0 {0 100} {1000 1200}\n"
     "end_cell\n"
-    "begin_cell {$4}\n"
-    "end_cell\n"
     "begin_cell {$3}\n"
     "sref {$1} 90 1 1 {-10 20}\n"
     "sref {$4} 90 1 1 {-10 20}\n"
@@ -1327,14 +1327,14 @@ TEST(116)
       "  {{name} {117}}\n"
       "}\n"
       "begin_libp $props 0.001\n"
+      "begin_cell {$2}\n"
+      "end_cell\n"
       "set props {\n"
       "  {42 {42}}\n"
       "}\n"
       "begin_cellp $props {$1}\n"
       "path 1 0 0 0 0 {0 100} {1000 1200}\n"
       "end_cell\n"
-      "begin_cell {$2}\n"
-      "end_cell\n"
       "end_lib\n"
     ;
 
@@ -1376,14 +1376,14 @@ TEST(116)
       "  {{name} {117}}\n"
       "}\n"
       "begin_libp $props 0.001\n"
+      "begin_cell {$2}\n"
+      "end_cell\n"
       "set props {\n"
       "  {42 {42}}\n"
       "}\n"
       "begin_cellp $props {$1}\n"
       "path 1 0 0 0 0 {0 100} {1000 1200}\n"
       "end_cell\n"
-      "begin_cell {$2}\n"
-      "end_cell\n"
       "end_lib\n"
     ;
 
@@ -1431,17 +1431,17 @@ TEST(116)
       "}\n"
       "begin_libp $props 0.001\n"
       "set props {\n"
+      "  {{S_BOUNDING_BOX} {2,0,0,0,0}}\n"
+      "}\n"
+      "begin_cellp $props {$2}\n"
+      "end_cell\n"
+      "set props {\n"
       "  {{S_BOUNDING_BOX} {0,0,100,1000,1100}}\n"
       "  {42 {42}}\n"
       "}\n"
       "begin_cellp $props {$1}\n"
       "path 1 0 0 0 0 {0 100} {1000 1200}\n"
       "end_cell\n"
-      "set props {\n"
-      "  {{S_BOUNDING_BOX} {2,0,0,0,0}}\n"
-      "}\n"
-      "begin_cellp $props {$2}\n"
-      "end_cell\n"
       "end_lib\n"
     ;
 
diff --git a/src/plugins/tools/view_25d/lay_plugin/D25View.ui b/src/plugins/tools/view_25d/lay_plugin/D25View.ui
new file mode 100644
index 000000000..f09a1a654
--- /dev/null
+++ b/src/plugins/tools/view_25d/lay_plugin/D25View.ui
@@ -0,0 +1,325 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<ui version="4.0">
+ <class>D25View</class>
+ <widget class="QDialog" name="D25View">
+  <property name="geometry">
+   <rect>
+    <x>0</x>
+    <y>0</y>
+    <width>854</width>
+    <height>665</height>
+   </rect>
+  </property>
+  <property name="windowTitle">
+   <string>2.5d View</string>
+  </property>
+  <layout class="QVBoxLayout">
+   <property name="spacing">
+    <number>6</number>
+   </property>
+   <property name="leftMargin">
+    <number>9</number>
+   </property>
+   <property name="topMargin">
+    <number>9</number>
+   </property>
+   <property name="rightMargin">
+    <number>9</number>
+   </property>
+   <property name="bottomMargin">
+    <number>9</number>
+   </property>
+   <item>
+    <widget class="QFrame" name="frame">
+     <property name="sizePolicy">
+      <sizepolicy hsizetype="Preferred" vsizetype="Fixed">
+       <horstretch>0</horstretch>
+       <verstretch>0</verstretch>
+      </sizepolicy>
+     </property>
+     <property name="frameShape">
+      <enum>QFrame::NoFrame</enum>
+     </property>
+     <property name="frameShadow">
+      <enum>QFrame::Raised</enum>
+     </property>
+     <layout class="QHBoxLayout" name="horizontalLayout_2">
+      <property name="spacing">
+       <number>6</number>
+      </property>
+      <property name="leftMargin">
+       <number>0</number>
+      </property>
+      <property name="topMargin">
+       <number>0</number>
+      </property>
+      <property name="rightMargin">
+       <number>0</number>
+      </property>
+      <property name="bottomMargin">
+       <number>0</number>
+      </property>
+      <item>
+       <widget class="QSlider" name="zoom_slider">
+        <property name="sizePolicy">
+         <sizepolicy hsizetype="Expanding" vsizetype="Fixed">
+          <horstretch>0</horstretch>
+          <verstretch>0</verstretch>
+         </sizepolicy>
+        </property>
+        <property name="maximumSize">
+         <size>
+          <width>150</width>
+          <height>16777215</height>
+         </size>
+        </property>
+        <property name="minimum">
+         <number>-300</number>
+        </property>
+        <property name="maximum">
+         <number>300</number>
+        </property>
+        <property name="orientation">
+         <enum>Qt::Horizontal</enum>
+        </property>
+       </widget>
+      </item>
+      <item>
+       <widget class="QLabel" name="zoom_factor">
+        <property name="sizePolicy">
+         <sizepolicy hsizetype="Fixed" vsizetype="Preferred">
+          <horstretch>0</horstretch>
+          <verstretch>0</verstretch>
+         </sizepolicy>
+        </property>
+        <property name="minimumSize">
+         <size>
+          <width>60</width>
+          <height>0</height>
+         </size>
+        </property>
+        <property name="text">
+         <string>%</string>
+        </property>
+       </widget>
+      </item>
+      <item>
+       <spacer name="horizontalSpacer">
+        <property name="orientation">
+         <enum>Qt::Horizontal</enum>
+        </property>
+        <property name="sizeType">
+         <enum>QSizePolicy::Expanding</enum>
+        </property>
+        <property name="sizeHint" stdset="0">
+         <size>
+          <width>5</width>
+          <height>20</height>
+         </size>
+        </property>
+       </spacer>
+      </item>
+      <item>
+       <widget class="QToolButton" name="fit_left">
+        <property name="text">
+         <string>...</string>
+        </property>
+        <property name="icon">
+         <iconset resource="../../../../lay/lay/layResources.qrc">
+          <normaloff>:/fit_left.png</normaloff>:/fit_left.png</iconset>
+        </property>
+        <property name="iconSize">
+         <size>
+          <width>24</width>
+          <height>24</height>
+         </size>
+        </property>
+        <property name="autoRaise">
+         <bool>true</bool>
+        </property>
+       </widget>
+      </item>
+      <item>
+       <widget class="QToolButton" name="fit_front">
+        <property name="text">
+         <string>...</string>
+        </property>
+        <property name="icon">
+         <iconset resource="../../../../lay/lay/layResources.qrc">
+          <normaloff>:/fit_front.png</normaloff>:/fit_front.png</iconset>
+        </property>
+        <property name="iconSize">
+         <size>
+          <width>24</width>
+          <height>24</height>
+         </size>
+        </property>
+        <property name="autoRaise">
+         <bool>true</bool>
+        </property>
+       </widget>
+      </item>
+      <item>
+       <widget class="QToolButton" name="fit_right">
+        <property name="text">
+         <string>...</string>
+        </property>
+        <property name="icon">
+         <iconset resource="../../../../lay/lay/layResources.qrc">
+          <normaloff>:/fit_right.png</normaloff>:/fit_right.png</iconset>
+        </property>
+        <property name="iconSize">
+         <size>
+          <width>24</width>
+          <height>24</height>
+         </size>
+        </property>
+        <property name="autoRaise">
+         <bool>true</bool>
+        </property>
+       </widget>
+      </item>
+      <item>
+       <widget class="QToolButton" name="fit_back">
+        <property name="text">
+         <string>...</string>
+        </property>
+        <property name="icon">
+         <iconset resource="../../../../lay/lay/layResources.qrc">
+          <normaloff>:/fit_back.png</normaloff>:/fit_back.png</iconset>
+        </property>
+        <property name="iconSize">
+         <size>
+          <width>24</width>
+          <height>24</height>
+         </size>
+        </property>
+        <property name="autoRaise">
+         <bool>true</bool>
+        </property>
+       </widget>
+      </item>
+      <item>
+       <widget class="QToolButton" name="fit_top">
+        <property name="text">
+         <string>...</string>
+        </property>
+        <property name="icon">
+         <iconset resource="../../../../lay/lay/layResources.qrc">
+          <normaloff>:/fit_top.png</normaloff>:/fit_top.png</iconset>
+        </property>
+        <property name="iconSize">
+         <size>
+          <width>24</width>
+          <height>24</height>
+         </size>
+        </property>
+        <property name="autoRaise">
+         <bool>true</bool>
+        </property>
+       </widget>
+      </item>
+      <item>
+       <widget class="QToolButton" name="fit_bottom">
+        <property name="text">
+         <string>...</string>
+        </property>
+        <property name="icon">
+         <iconset resource="../../../../lay/lay/layResources.qrc">
+          <normaloff>:/fit_bottom.png</normaloff>:/fit_bottom.png</iconset>
+        </property>
+        <property name="iconSize">
+         <size>
+          <width>24</width>
+          <height>24</height>
+         </size>
+        </property>
+        <property name="autoRaise">
+         <bool>true</bool>
+        </property>
+       </widget>
+      </item>
+     </layout>
+    </widget>
+   </item>
+   <item>
+    <widget class="lay::D25ViewWidget" name="d25_view"/>
+   </item>
+   <item>
+    <widget class="QFrame" name="frame_2">
+     <property name="sizePolicy">
+      <sizepolicy hsizetype="Preferred" vsizetype="Fixed">
+       <horstretch>0</horstretch>
+       <verstretch>0</verstretch>
+      </sizepolicy>
+     </property>
+     <property name="frameShape">
+      <enum>QFrame::NoFrame</enum>
+     </property>
+     <property name="frameShadow">
+      <enum>QFrame::Raised</enum>
+     </property>
+     <layout class="QHBoxLayout" name="horizontalLayout">
+      <property name="leftMargin">
+       <number>0</number>
+      </property>
+      <property name="topMargin">
+       <number>0</number>
+      </property>
+      <property name="rightMargin">
+       <number>0</number>
+      </property>
+      <property name="bottomMargin">
+       <number>0</number>
+      </property>
+      <item>
+       <widget class="QLabel" name="label">
+        <property name="text">
+         <string>Press and hold SHIFT for top view</string>
+        </property>
+       </widget>
+      </item>
+      <item>
+       <widget class="QDialogButtonBox" name="buttonBox">
+        <property name="orientation">
+         <enum>Qt::Horizontal</enum>
+        </property>
+        <property name="standardButtons">
+         <set>QDialogButtonBox::Close</set>
+        </property>
+       </widget>
+      </item>
+     </layout>
+    </widget>
+   </item>
+  </layout>
+ </widget>
+ <customwidgets>
+  <customwidget>
+   <class>lay::D25ViewWidget</class>
+   <extends>QOpenGLWidget</extends>
+   <header>layD25ViewWidget.h</header>
+  </customwidget>
+ </customwidgets>
+ <resources>
+  <include location="../../../../lay/lay/layResources.qrc"/>
+ </resources>
+ <connections>
+  <connection>
+   <sender>buttonBox</sender>
+   <signal>rejected()</signal>
+   <receiver>D25View</receiver>
+   <slot>accept()</slot>
+   <hints>
+    <hint type="sourcelabel">
+     <x>530</x>
+     <y>626</y>
+    </hint>
+    <hint type="destinationlabel">
+     <x>443</x>
+     <y>643</y>
+    </hint>
+   </hints>
+  </connection>
+ </connections>
+</ui>
diff --git a/src/plugins/tools/view_25d/lay_plugin/layD25Camera.cc b/src/plugins/tools/view_25d/lay_plugin/layD25Camera.cc
new file mode 100644
index 000000000..f2d358c8d
--- /dev/null
+++ b/src/plugins/tools/view_25d/lay_plugin/layD25Camera.cc
@@ -0,0 +1,113 @@
+
+/*
+
+  KLayout Layout Viewer
+  Copyright (C) 2006-2020 Matthias Koefferlein
+
+  This program is free software; you can redistribute it and/or modify
+  it under the terms of the GNU General Public License as published by
+  the Free Software Foundation; either version 2 of the License, or
+  (at your option) any later version.
+
+  This program is distributed in the hope that it will be useful,
+  but WITHOUT ANY WARRANTY; without even the implied warranty of
+  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+  GNU General Public License for more details.
+
+  You should have received a copy of the GNU General Public License
+  along with this program; if not, write to the Free Software
+  Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
+
+*/
+
+
+#include "layD25Camera.h"
+
+#include <QWidget>
+
+#include "math.h"
+
+namespace lay
+{
+
+D25Camera::D25Camera ()
+{
+  init ();
+}
+
+D25Camera::~D25Camera ()
+{
+  //  .. nothing yet ..
+}
+
+void
+D25Camera::init ()
+{
+  m_fov = 90.0;
+  m_cam_azimuth = m_cam_elevation = 0.0;
+  m_top_view = false;
+}
+
+void
+D25Camera::camera_reset ()
+{
+  init ();
+  camera_changed ();
+}
+
+double
+D25Camera::cam_fov () const
+{
+  return m_fov;
+}
+
+double
+D25Camera::cam_dist () const
+{
+  return 4.0;
+}
+
+QVector3D
+D25Camera::cam_direction () const
+{
+  return cam_trans ().inverted ().map (QVector3D (0, 0, -1));
+}
+
+QVector3D
+D25Camera::cam_position () const
+{
+  return cam_direction () * -cam_dist ();
+}
+
+double
+D25Camera::cam_azimuth () const
+{
+  return m_cam_azimuth;
+}
+
+double
+D25Camera::cam_elevation () const
+{
+  return m_top_view ? -90.0 : m_cam_elevation;
+}
+
+QMatrix4x4
+D25Camera::cam_perspective () const
+{
+  QMatrix4x4 t;
+  t.perspective (cam_fov (), aspect_ratio (), 0.1f, 10000.0f);
+  t.translate (QVector3D (0.0, 0.0, -cam_dist ()));
+  return t;
+}
+
+QMatrix4x4
+D25Camera::cam_trans () const
+{
+  QMatrix4x4 t;
+  t.rotate (-cam_elevation (), 1.0, 0.0, 0.0);
+  t.rotate (cam_azimuth (), 0.0, 1.0, 0.0);
+  return t;
+}
+
+}
+
diff --git a/src/plugins/tools/view_25d/lay_plugin/layD25Camera.h b/src/plugins/tools/view_25d/lay_plugin/layD25Camera.h
new file mode 100644
index 000000000..06680ef47
--- /dev/null
+++ b/src/plugins/tools/view_25d/lay_plugin/layD25Camera.h
@@ -0,0 +1,142 @@
+
+/*
+
+  KLayout Layout Viewer
+  Copyright (C) 2006-2020 Matthias Koefferlein
+
+  This program is free software; you can redistribute it and/or modify
+  it under the terms of the GNU General Public License as published by
+  the Free Software Foundation; either version 2 of the License, or
+  (at your option) any later version.
+
+  This program is distributed in the hope that it will be useful,
+  but WITHOUT ANY WARRANTY; without even the implied warranty of
+  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+  GNU General Public License for more details.
+
+  You should have received a copy of the GNU General Public License
+  along with this program; if not, write to the Free Software
+  Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
+
+*/
+
+#ifndef HDR_layD25Camera
+#define HDR_layD25Camera
+
+#include "layPluginCommon.h"
+
+#include <QMatrix4x4>
+#include <QVector3D>
+
+namespace lay
+{
+
+class LAY_PLUGIN_PUBLIC D25Camera
+{
+public:
+  D25Camera ();
+  virtual ~D25Camera ();
+
+  /**
+   *  @brief Gets the position of the camera objective in the scene coordinate system
+   */
+  QVector3D cam_position () const;
+
+  /**
+   *  @brief Gets the direction the camera looks into in the scene coordinate system
+   */
+  QVector3D cam_direction () const;
+
+  /**
+   *  @brief Gets the perspective part of the transformation applied transform scene coordinates into the image plane
+   *  The full transformation for scene to image plane is cam_perspective * cam_trans.
+   */
+  QMatrix4x4 cam_perspective () const;
+
+  /**
+   *  @brief Gets the azimuth/elevation part of the transformation applied transform scene coordinates into the image plane
+   *  The full transformation for scene to image plane is cam_perspective * cam_trans.
+   */
+  QMatrix4x4 cam_trans () const;
+
+  /**
+   *  @brief Gets the distance of the objective in scene coordinates
+   */
+  double cam_dist () const;
+
+  /**
+   *  @brief Gets the field of view of the camera
+   *  The field of view is the objective opening angle.
+   */
+  double cam_fov () const;
+
+  /**
+   *  @brief Gets a flag indicating whether top view is enabled
+   *  In "top view" mode, the elevation is fixed to -90 degree.
+   */
+  bool top_view () const
+  {
+    return m_top_view;
+  }
+
+  /**
+   *  @brief Sets a flag indicating whether top view is enabled
+   */
+  void set_top_view (bool f)
+  {
+    m_top_view = f;
+    camera_changed ();
+  }
+
+  /**
+   *  @brief Gets the elevation angle
+   *  A negative angle means the camera looks down, a positive angle means it looks up.
+   */
+  double cam_elevation () const;
+
+  /**
+   *  @brief Sets the elevation angle
+   */
+  void set_cam_elevation (double e)
+  {
+    m_cam_elevation = e;
+    camera_changed ();
+  }
+
+  /**
+   *  @brief Gets the azimuth angle
+   *  A positive angle means we look from the left. A negative means we look from the right.
+   */
+  double cam_azimuth () const;
+
+  /**
+   *  @brief Sets the azimuth angle
+   */
+  void set_cam_azimuth (double a)
+  {
+    m_cam_azimuth = a;
+    camera_changed ();
+  }
+
+  /**
+   *  @brief Resets the camera's orientation
+   */
+  void camera_reset ();
+
+protected:
+  virtual void camera_changed () { }
+  virtual double aspect_ratio () const { return 1.0; }
+
+private:
+  double m_cam_azimuth, m_cam_elevation;
+  bool m_top_view;
+  QVector3D m_displacement;
+  double m_fov;
+
+  void init ();
+};
+
+}
+
+#endif
+
diff --git a/src/plugins/tools/view_25d/lay_plugin/layD25MemChunks.cc b/src/plugins/tools/view_25d/lay_plugin/layD25MemChunks.cc
new file mode 100644
index 000000000..dfe8fb146
--- /dev/null
+++ b/src/plugins/tools/view_25d/lay_plugin/layD25MemChunks.cc
@@ -0,0 +1,24 @@
+
+/*
+
+  KLayout Layout Viewer
+  Copyright (C) 2006-2020 Matthias Koefferlein
+
+  This program is free software; you can redistribute it and/or modify
+  it under the terms of the GNU General Public License as published by
+  the Free Software Foundation; either version 2 of the License, or
+  (at your option) any later version.
+
+  This program is distributed in the hope that it will be useful,
+  but WITHOUT ANY WARRANTY; without even the implied warranty of
+  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+  GNU General Public License for more details.
+
+  You should have received a copy of the GNU General Public License
+  along with this program; if not, write to the Free Software
+  Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
+
+*/
+
+#include "layD25MemChunks.h"
+
diff --git a/src/plugins/tools/view_25d/lay_plugin/layD25MemChunks.h b/src/plugins/tools/view_25d/lay_plugin/layD25MemChunks.h
new file mode 100644
index 000000000..945d1338d
--- /dev/null
+++ b/src/plugins/tools/view_25d/lay_plugin/layD25MemChunks.h
@@ -0,0 +1,266 @@
+
+/*
+
+  KLayout Layout Viewer
+  Copyright (C) 2006-2020 Matthias Koefferlein
+
+  This program is free software; you can redistribute it and/or modify
+  it under the terms of the GNU General Public License as published by
+  the Free Software Foundation; either version 2 of the License, or
+  (at your option) any later version.
+
+  This program is distributed in the hope that it will be useful,
+  but WITHOUT ANY WARRANTY; without even the implied warranty of
+  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+  GNU General Public License for more details.
+
+  You should have received a copy of the GNU General Public License
+  along with this program; if not, write to the Free Software
+  Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
+
+*/
+
+#ifndef HDR_layD25MemChunks
+#define HDR_layD25MemChunks
+
+#include <QDialog>
+#include <QOpenGLFunctions>
+
+#include "tlObject.h"
+#include <string.h>  //  for memcpy
+
+namespace lay
+{
+
+template <class Obj>
+struct gl_type2enum
+{
+  GLenum operator() () const;
+};
+
+template <>
+struct gl_type2enum<float>
+{
+  GLenum operator() () const { return GL_FLOAT; }
+};
+
+
+/**
+ *  @brief Provides a semi-contiguous array of objects
+ *
+ *  The objects are kept in chunks of ChunkLen items.
+ *  The blocks can be accessed individually. The array can be
+ *  cleared and new items can be added. No insert or delete.
+ *
+ *  This object is intended to be used for keeping vertex,
+ *  color or point data for OpenGL.
+ */
+template <class Obj, size_t ChunkLen = 1024>
+class mem_chunks
+  : public QDialog
+{
+public:
+
+  struct chunk {
+  public:
+    chunk ()
+      : m_len (0), m_next (0)
+    {
+      //  .. nothing yet ..
+    }
+
+    chunk (const chunk &other)
+      : m_len (0), m_next (0)
+    {
+      operator= (other);
+    }
+
+    chunk &operator= (const chunk &other)
+    {
+      if (this != &other) {
+        memcpy (&m_objects, &other.m_objects, sizeof (m_objects));
+        m_len = other.m_len;
+      }
+      return *this;
+    }
+
+    const Obj *front () const { return m_objects; }
+    size_t size () const { return m_len; }
+    const chunk *next () const { return m_next; }
+
+  private:
+    friend class mem_chunks;
+
+    Obj m_objects [ChunkLen];
+    size_t m_len;
+    chunk *m_next;
+  };
+
+  class iterator
+  {
+  public:
+    iterator (chunk *ch = 0)
+      : mp_chunk (ch)
+    {
+      //  .. nothing yet ..
+    }
+
+    bool operator== (iterator other) const
+    {
+      return mp_chunk == other.mp_chunk;
+    }
+
+    bool operator!= (iterator other) const
+    {
+      return mp_chunk != other.mp_chunk;
+    }
+
+    const chunk &operator* () const
+    {
+      return *mp_chunk;
+    }
+
+    const chunk *operator-> () const
+    {
+      return mp_chunk;
+    }
+
+    void operator++ ()
+    {
+      mp_chunk = mp_chunk->next ();
+    }
+
+  private:
+    const chunk *mp_chunk;
+  };
+
+  /**
+   *  @brief Default constructor
+   *  Creates an empty array
+   */
+  mem_chunks ()
+    : mp_chunks (0), mp_last_chunk (0)
+  {
+    //  .. nothing yet ..
+  }
+
+  /**
+   *  @brief Destructor
+   */
+  ~mem_chunks ()
+  {
+    clear ();
+  }
+
+  /**
+   *  @brief Copy constructor
+   */
+  mem_chunks (const mem_chunks &other)
+    : mp_chunks (0), mp_last_chunk (0)
+  {
+    operator= (other);
+  }
+
+  /**
+   *  @brief Assignment
+   */
+  mem_chunks &operator= (const mem_chunks &other)
+  {
+    if (this != &other) {
+      clear ();
+      const chunk *ch = other.mp_chunks;
+      while (ch) {
+        if (! mp_chunks) {
+          mp_last_chunk = mp_chunks = new chunk (*ch);
+        } else {
+          mp_last_chunk->m_next = new chunk (*ch);
+          mp_last_chunk = mp_last_chunk->m_next;
+        }
+        ch = ch->next ();
+      }
+    }
+
+    return *this;
+  }
+
+  /**
+   *  @brief Clears the array
+   */
+  void clear ()
+  {
+    chunk *ch = mp_chunks;
+    mp_chunks = 0;
+    mp_last_chunk = 0;
+    while (ch) {
+      chunk *del = ch;
+      ch = ch->m_next;
+      delete del;
+    }
+  }
+
+  /**
+   *  @brief Adds an element to the array
+   */
+  void add (const Obj &element)
+  {
+    if (! mp_last_chunk) {
+      mp_chunks = mp_last_chunk = new chunk ();
+    }
+
+    if (mp_last_chunk->m_len >= ChunkLen) {
+      mp_last_chunk->m_next = new chunk ();
+      mp_last_chunk = mp_last_chunk->m_next;
+    }
+
+    mp_last_chunk->m_objects [mp_last_chunk->m_len++] = element;
+  }
+
+  /**
+   *  @brief Adds two elements
+   */
+  void add (const Obj &e1, const Obj &e2)
+  {
+    add (e1);
+    add (e2);
+  }
+
+  /**
+   *  @brief Adds three elements
+   */
+  void add (const Obj &e1, const Obj &e2, const Obj &e3)
+  {
+    add (e1);
+    add (e2);
+    add (e3);
+  }
+
+  /**
+   *  @brief begin iterator
+   */
+  iterator begin () const { return iterator (mp_chunks); }
+
+  /**
+   *  @brief end iterator
+   */
+  iterator end () const { return iterator (); }
+
+  /**
+   *  @brief Draw to the given context
+   */
+  void draw_to (QOpenGLFunctions *ctx, GLuint location, GLenum mode) const
+  {
+    for (iterator c = begin (); c != end (); ++c) {
+      ctx->glVertexAttribPointer (location, 3, gl_type2enum<Obj> () (), GL_FALSE, 0, c->front ());
+      ctx->glDrawArrays (mode, 0, c->size () / 3);
+    }
+  }
+
+private:
+  chunk *mp_chunks;
+  chunk *mp_last_chunk;
+};
+
+}
+
+#endif
+
diff --git a/src/plugins/tools/view_25d/lay_plugin/layD25Plugin.cc b/src/plugins/tools/view_25d/lay_plugin/layD25Plugin.cc
new file mode 100644
index 000000000..c2042a2f4
--- /dev/null
+++ b/src/plugins/tools/view_25d/lay_plugin/layD25Plugin.cc
@@ -0,0 +1,114 @@
+
+/*
+
+  KLayout Layout Viewer
+  Copyright (C) 2006-2020 Matthias Koefferlein
+
+  This program is free software; you can redistribute it and/or modify
+  it under the terms of the GNU General Public License as published by
+  the Free Software Foundation; either version 2 of the License, or
+  (at your option) any later version.
+
+  This program is distributed in the hope that it will be useful,
+  but WITHOUT ANY WARRANTY; without even the implied warranty of
+  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+  GNU General Public License for more details.
+
+  You should have received a copy of the GNU General Public License
+  along with this program; if not, write to the Free Software
+  Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
+
+*/
+
+
+
+#include "layD25View.h"
+#include "layDispatcher.h"
+
+#include "layPlugin.h"
+
+#include <QSurfaceFormat>
+
+namespace lay
+{
+
+class D25Plugin
+  : public lay::Plugin
+{
+public:
+  D25Plugin (Plugin *parent, lay::LayoutView *view)
+    : lay::Plugin (parent), mp_view (view)
+  {
+    mp_dialog = new lay::D25View (0);
+  }
+
+  ~D25Plugin ()
+  {
+    delete mp_dialog;
+    mp_dialog = 0;
+  }
+
+  void menu_activated (const std::string &symbol) 
+  {
+    if (symbol == "lay::d25_view") {
+
+      if (mp_dialog->exec_dialog (mp_view)) {
+
+        // ... implementation is in layD25ToolDialog.cc ...
+
+      }
+
+    }
+  }
+
+private:
+  lay::LayoutView *mp_view;
+  lay::D25View *mp_dialog;
+};
+
+class D25PluginDeclaration
+  : public lay::PluginDeclaration
+{
+public:
+  D25PluginDeclaration ()
+  {
+    //  .. nothing yet ..
+  }
+  
+  virtual void get_options (std::vector < std::pair<std::string, std::string> > & /*options*/) const
+  {
+    //  .. nothing yet ..
+  }
+
+  virtual lay::ConfigPage *config_page (QWidget * /*parent*/, std::string & /*title*/) const
+  {
+    // .. nothing yet ..
+    return 0;
+  }
+
+  virtual void get_menu_entries (std::vector<lay::MenuEntry> &menu_entries) const
+  {
+    lay::PluginDeclaration::get_menu_entries (menu_entries);
+    menu_entries.push_back (lay::menu_item ("lay::d25_view", "d25_view:edit", "tools_menu.post_verification_group", tl::to_string (QObject::tr ("2.5d View"))));
+  }
+
+  virtual bool configure (const std::string & /*name*/, const std::string & /*value*/)
+  {
+    return false;
+  }
+
+  virtual void config_finalize ()
+  {
+    // .. nothing yet ..
+  }
+
+  lay::Plugin *create_plugin (db::Manager *, lay::Dispatcher *root, lay::LayoutView *view) const
+  {
+    return new D25Plugin (root, view);
+  }
+};
+
+static tl::RegisteredClass<lay::PluginDeclaration> config_decl (new lay::D25PluginDeclaration (), 3100, "lay::D25Plugin");
+
+}
+
diff --git a/src/plugins/tools/view_25d/lay_plugin/layD25View.cc b/src/plugins/tools/view_25d/lay_plugin/layD25View.cc
new file mode 100644
index 000000000..fd8d57bac
--- /dev/null
+++ b/src/plugins/tools/view_25d/lay_plugin/layD25View.cc
@@ -0,0 +1,151 @@
+
+/*
+
+  KLayout Layout Viewer
+  Copyright (C) 2006-2020 Matthias Koefferlein
+
+  This program is free software; you can redistribute it and/or modify
+  it under the terms of the GNU General Public License as published by
+  the Free Software Foundation; either version 2 of the License, or
+  (at your option) any later version.
+
+  This program is distributed in the hope that it will be useful,
+  but WITHOUT ANY WARRANTY; without even the implied warranty of
+  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+  GNU General Public License for more details.
+
+  You should have received a copy of the GNU General Public License
+  along with this program; if not, write to the Free Software
+  Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
+
+*/
+
+
+#include "layD25View.h"
+#include "layLayoutView.h"
+
+#include "ui_D25View.h"
+
+#include <stdio.h>
+
+namespace lay
+{
+
+const double initial_elevation = 3.0;
+
+D25View::D25View (QWidget *parent)
+  : QDialog (parent)
+{
+  mp_ui = new Ui::D25View ();
+  mp_ui->setupUi (this);
+
+  mp_ui->d25_view->setFocusPolicy (Qt::StrongFocus);
+  mp_ui->d25_view->setFocus ();
+
+  connect (mp_ui->fit_back, SIGNAL (clicked ()), this, SLOT (fit_button_clicked ()));
+  connect (mp_ui->fit_front, SIGNAL (clicked ()), this, SLOT (fit_button_clicked ()));
+  connect (mp_ui->fit_left, SIGNAL (clicked ()), this, SLOT (fit_button_clicked ()));
+  connect (mp_ui->fit_right, SIGNAL (clicked ()), this, SLOT (fit_button_clicked ()));
+  connect (mp_ui->fit_top, SIGNAL (clicked ()), this, SLOT (fit_button_clicked ()));
+  connect (mp_ui->fit_bottom, SIGNAL (clicked ()), this, SLOT (fit_button_clicked ()));
+  connect (mp_ui->zoom_slider, SIGNAL (valueChanged (int)), this, SLOT (scale_slider_changed (int)));
+  connect (mp_ui->d25_view, SIGNAL (scale_factor_changed (double)), this, SLOT (scale_factor_changed (double)));
+}
+
+D25View::~D25View ()
+{
+  delete mp_ui;
+  mp_ui = 0;
+}
+
+static QString scale_factor_to_string (double f)
+{
+  QString s;
+  s.sprintf ("x %.3g", f);
+  return s;
+}
+
+void
+D25View::scale_slider_changed (int value)
+{
+  double f = exp (log (10.0) * -0.01 * value);
+  mp_ui->zoom_factor->setText (scale_factor_to_string (f));
+  mp_ui->d25_view->set_scale_factor (f);
+}
+
+void
+D25View::scale_factor_changed (double f)
+{
+  mp_ui->zoom_factor->setText (scale_factor_to_string (f));
+  int v = floor (0.5 - log10 (f) * 100.0);
+  mp_ui->zoom_slider->blockSignals (true);
+  mp_ui->zoom_slider->setValue (v);
+  mp_ui->zoom_slider->blockSignals (false);
+}
+
+int 
+D25View::exec_dialog (lay::LayoutView *view)
+{
+  mp_view.reset (view);
+  bool any = mp_ui->d25_view->attach_view (view);
+
+  if (! any) {
+
+    mp_view.reset (0);
+    mp_ui->d25_view->attach_view (0);
+
+    throw tl::Exception (tl::to_string (tr ("No z data configured for the layers in the view.\nUse \"Tools/Manage Technologies\" to set up a z stack.")));
+
+  }
+
+  mp_ui->d25_view->reset ();
+  mp_ui->d25_view->set_cam_azimuth (0.0);
+  mp_ui->d25_view->set_cam_elevation (initial_elevation);
+  mp_ui->d25_view->fit ();
+
+  int ret = QDialog::exec ();
+
+  mp_ui->d25_view->attach_view (0);
+  mp_view.reset (0);
+
+  return ret;
+}
+
+void
+D25View::fit_button_clicked ()
+{
+  double azimuth = mp_ui->d25_view->cam_azimuth ();
+  double elevation = mp_ui->d25_view->cam_elevation ();
+
+  if (sender () == mp_ui->fit_back) {
+    azimuth = -180.0;
+    elevation = -initial_elevation;
+  } else if (sender () == mp_ui->fit_front) {
+    azimuth = 0.0;
+    elevation = -initial_elevation;
+  } else if (sender () == mp_ui->fit_left) {
+    azimuth = 90.0;
+    elevation = -initial_elevation;
+  } else if (sender () == mp_ui->fit_right) {
+    azimuth = -90.0;
+    elevation = -initial_elevation;
+  } else if (sender () == mp_ui->fit_top) {
+    elevation = -90;
+  } else if (sender () == mp_ui->fit_bottom) {
+    elevation = 90;
+  }
+
+  mp_ui->d25_view->set_cam_azimuth (azimuth);
+  mp_ui->d25_view->set_cam_elevation (elevation);
+
+  mp_ui->d25_view->fit ();
+}
+
+void 
+D25View::accept ()
+{
+  QDialog::accept ();
+}
+
+}
+
diff --git a/src/plugins/tools/view_25d/lay_plugin/layD25View.h b/src/plugins/tools/view_25d/lay_plugin/layD25View.h
new file mode 100644
index 000000000..6f776ed3c
--- /dev/null
+++ b/src/plugins/tools/view_25d/lay_plugin/layD25View.h
@@ -0,0 +1,70 @@
+
+/*
+
+  KLayout Layout Viewer
+  Copyright (C) 2006-2020 Matthias Koefferlein
+
+  This program is free software; you can redistribute it and/or modify
+  it under the terms of the GNU General Public License as published by
+  the Free Software Foundation; either version 2 of the License, or
+  (at your option) any later version.
+
+  This program is distributed in the hope that it will be useful,
+  but WITHOUT ANY WARRANTY; without even the implied warranty of
+  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+  GNU General Public License for more details.
+
+  You should have received a copy of the GNU General Public License
+  along with this program; if not, write to the Free Software
+  Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
+
+*/
+
+#ifndef HDR_layD25View
+#define HDR_layD25View
+
+#include <QDialog>
+
+#include "tlObject.h"
+
+namespace Ui
+{
+  class D25View;
+}
+
+namespace lay
+{
+  class LayoutView;
+}
+
+namespace lay
+{
+
+class D25View
+  : public QDialog
+{
+Q_OBJECT 
+
+public:
+  D25View (QWidget *parent);
+  ~D25View ();
+
+  int exec_dialog (lay::LayoutView *view);
+
+protected:
+  void accept ();
+
+private slots:
+  void fit_button_clicked ();
+  void scale_factor_changed (double f);
+  void scale_slider_changed (int value);
+
+private:
+  Ui::D25View *mp_ui;
+  tl::weak_ptr<lay::LayoutView> mp_view;
+};
+
+}
+
+#endif
+
diff --git a/src/plugins/tools/view_25d/lay_plugin/layD25ViewUtils.cc b/src/plugins/tools/view_25d/lay_plugin/layD25ViewUtils.cc
new file mode 100644
index 000000000..3fb6e8dca
--- /dev/null
+++ b/src/plugins/tools/view_25d/lay_plugin/layD25ViewUtils.cc
@@ -0,0 +1,228 @@
+
+/*
+
+  KLayout Layout Viewer
+  Copyright (C) 2006-2020 Matthias Koefferlein
+
+  This program is free software; you can redistribute it and/or modify
+  it under the terms of the GNU General Public License as published by
+  the Free Software Foundation; either version 2 of the License, or
+  (at your option) any later version.
+
+  This program is distributed in the hope that it will be useful,
+  but WITHOUT ANY WARRANTY; without even the implied warranty of
+  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+  GNU General Public License for more details.
+
+  You should have received a copy of the GNU General Public License
+  along with this program; if not, write to the Free Software
+  Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
+
+*/
+
+#include "layD25ViewUtils.h"
+
+#include <QMatrix4x4>
+#include <QMatrix3x3>
+
+#include <math.h>
+
+namespace lay
+{
+
+const double epsilon = 1e-10;
+
+std::pair<bool, QVector3D>
+cutpoint_line_with_plane (const QVector3D &line, const QVector3D &dir, const QVector3D &plane, const QVector3D &plane_normal)
+{
+  double dn = QVector3D::dotProduct (dir, plane_normal);
+  if (fabs (dn) < epsilon) {
+    return std::make_pair (false, QVector3D ());
+  } else {
+    return std::make_pair (true, line + dir * QVector3D::dotProduct (plane - line, plane_normal) / dn);
+  }
+}
+
+std::pair<bool, QVector3D>
+cutpoint_line_with_face (const QVector3D &line, const QVector3D &dir, const QVector3D &plane, const QVector3D &u, const QVector3D &v)
+{
+  QVector3D n = QVector3D::crossProduct (u, v);
+  std::pair<bool, QVector3D> r = cutpoint_line_with_plane (line, dir, plane, n);
+  if (! r.first) {
+    return r;
+  }
+
+  double pu = QVector3D::dotProduct (r.second - plane, u);
+  double pv = QVector3D::dotProduct (r.second - plane, v);
+
+  //  test whether the cut point is inside the face
+  if (pu < -epsilon || pu > u.lengthSquared () + epsilon || pv < -epsilon || pv > v.lengthSquared () + epsilon) {
+    return std::make_pair (false, QVector3D ());
+  } else {
+    return r;
+  }
+}
+
+static bool somewhat_perpendicular (const QVector3D &a, const QVector3D &b)
+{
+  //  returns true if a and b are perpendicular within +/-30 degree
+  return fabs (QVector3D::dotProduct (a, b)) < 0.5 * a.length () * b.length ();
+}
+
+static std::pair<bool, QVector3D> plane_or_face (const QVector3D &line, const QVector3D &line_dir, const QVector3D &corner, const QVector3D &u, const QVector3D &v, bool face)
+{
+  if (face) {
+    return cutpoint_line_with_face (line, line_dir, corner, u, v);
+  } else if (somewhat_perpendicular (u, line_dir) && somewhat_perpendicular (v, line_dir)) {
+    return cutpoint_line_with_plane (line, line_dir, corner, QVector3D::crossProduct (u, v));
+  } else {
+    return std::make_pair (false, QVector3D ());
+  }
+}
+
+std::pair<bool, QVector3D>
+hit_point_with_cuboid (const QVector3D &line, const QVector3D &line_dir, const QVector3D &corner, const QVector3D &dim)
+{
+  std::vector<std::pair<bool, QVector3D> > cutpoints;
+  cutpoints.reserve (6);  //  6 faces
+
+  for (int pass = 0; pass < 2; ++pass) {
+
+    bool face = (pass == 0);
+
+    if (face) {
+      bool in_x = (line.x () > corner.x () - epsilon) && (line.x () < corner.x () + dim.x () + epsilon);
+      bool in_y = (line.y () > corner.y () - epsilon) && (line.y () < corner.y () + dim.y () + epsilon);
+      bool in_z = (line.z () > corner.z () - epsilon) && (line.z () < corner.z () + dim.z () + epsilon);
+      if (in_x && in_y && in_z) {
+        //  inside cuboid
+        return std::make_pair (true, line);
+      }
+    }
+
+    cutpoints.clear ();
+
+    //  front
+    cutpoints.push_back (plane_or_face (line, line_dir, corner, QVector3D (dim.x (), 0, 0), QVector3D (0, dim.y (), 0), face));
+    //  back
+    cutpoints.push_back (plane_or_face (line, line_dir, corner + QVector3D (0, 0, dim.z ()), QVector3D (dim.x (), 0, 0), QVector3D (0, dim.y (), 0), face));
+    //  bottom
+    cutpoints.push_back (plane_or_face (line, line_dir, corner, QVector3D (dim.x (), 0, 0), QVector3D (0, 0, dim.z ()), face));
+    //  top
+    cutpoints.push_back (plane_or_face (line, line_dir, corner + QVector3D (0, dim.y (), 0), QVector3D (dim.x (), 0, 0), QVector3D (0, 0, dim.z ()), face));
+    //  left
+    cutpoints.push_back (plane_or_face (line, line_dir, corner, QVector3D (0, 0, dim.z ()), QVector3D (0, dim.y (), 0), face));
+    //  right
+    cutpoints.push_back (plane_or_face (line, line_dir, corner + QVector3D (dim.x (), 0, 0), QVector3D (0, 0, dim.z ()), QVector3D (0, dim.y (), 0), face));
+
+    double min_dist = 0.0;
+    int min_dist_index = -1;
+    QVector3D ld_norm = line_dir.normalized ();
+
+    for (std::vector<std::pair<bool, QVector3D> >::const_iterator i = cutpoints.begin (); i != cutpoints.end (); ++i) {
+      if (i->first) {
+        double dist = QVector3D::dotProduct (i->second - line, ld_norm);
+        if (min_dist_index < 0) {
+          min_dist = dist;
+          min_dist_index = int (i - cutpoints.begin ());
+        } else if (dist < min_dist) {
+          min_dist = dist;
+          min_dist_index = int (i - cutpoints.begin ());
+        }
+      }
+    }
+
+    if (min_dist_index >= 0) {
+      return cutpoints [min_dist_index];
+    }
+
+  }
+
+  return std::make_pair (false, QVector3D ());
+}
+
+std::pair<QVector3D, QVector3D>
+camera_normal (const QMatrix4x4 &camera_trans, double x, double y)
+{
+  QVector3D p = camera_trans.inverted ().map (QVector3D (x, y, 1.0));
+
+  QVector4D pv = camera_trans.row (3);
+
+  QMatrix4x4 m (camera_trans);
+
+  float values[] = {
+    float (x * pv.x ()),  float (x * pv.y ()),  float (x * pv.z ()),  0.0f,
+    float (y * pv.x ()),  float (y * pv.y ()),  float (y * pv.z ()),  0.0f,
+    float (pv.x ()),      float (pv.y ()),      float (pv.z ()),      0.0f,
+    0.0f,                 0.0f,                 0.0f,                 0.0f
+  };
+  m -= QMatrix4x4 (values);
+
+  QMatrix3x3 nm = m.normalMatrix ();
+
+  QVector3D u (nm (2, 0), nm (2, 1), nm (2, 2));
+  return (std::make_pair (p, u.normalized ()));
+}
+
+void
+normalize_scene_trans (const QMatrix4x4 &cam_trans, QVector3D &displacement, double &scale, double ztarget)
+{
+  //  Here is the theory:
+  //  Let:
+  //    cam = (  M  t  )     M = 3x3 matrix, t = 3x1 translation vector, z = scalar, p = 1x3 perspective
+  //          (  p  z  )
+  //  and:
+  //    scene = (  S  d*s  )   S = s*U1  (s = scale factor, U1 = 3x3 unit matrix), d = 3x1 displacement vector
+  //            (  0  1    )
+  //  then:
+  //    cam * scene = (  M*s   M*d*s+t  )
+  //                  (  p*s   p*d*s+z  )    (p*d = dot product)
+  //
+  //  this is image invariant (only x,y results are considered) against changes of s (s->s') if
+  //
+  //    1.) (p*d*s+z)/s = (p*d'*s'+z)/s'  (because x and y will be devided by this value)
+  //    2.) (M*d*s+t)/s = (M*d'*s'+t)/s'  for  [x] and [y]
+  //
+  //  or
+  //
+  //    1.) p*d+z/s = p*d'+z/s'
+  //    2.) M*d+t/s = M*d'+t/s'
+  //
+  //  If we seek a solution with d'[z] == b  (b = ztarget), we get these equations (f:=1/s')
+  //
+  //    2.)   M[xx] * d'[x] + M[xy] * d'[y] + t[x] * f = (M*d)[x] + t[x]/s - M[xz]*b
+  //          M[yx] * d'[x] + M[yy] * d'[y] + t[y] * f = (M*d)[y] + t[y]/s - M[yz]*b
+  //    1.)   p[x]  * d'[x] + p[y]  * d'[y] + z    * f = p*d      + z/s    - p[z]*b
+  //
+  //  we can solve these equations for d'[x], d'[y] and f.
+  //  With p[x]=M[wx], p[y]=M[wy] and z=t[w], the above equation system can be written as
+  //
+  //          M[ix] * d'[x] + M[iy] * d'[y] + t[i] * f = (M*d)[i] - M[iz]*b + t[i]/s   i = x,y,w
+  //
+
+  QMatrix4x4 m;
+
+  for (int i = 0; i < 4; ++i) {
+    if (i != 2) {
+      m (i, 0) = cam_trans (i, 0);
+      m (i, 1) = cam_trans (i, 1);
+      m (i, 3) = cam_trans (i, 3);
+    }
+  }
+
+  bool invertable = false;
+  QMatrix4x4 minv = m.inverted (&invertable);
+  if (! invertable) {
+    return;
+  }
+
+  QVector4D rhs = cam_trans.map (QVector4D (displacement.x (), displacement.y (), displacement.z () - ztarget, 1.0 / scale));
+  QVector4D sol = minv.map (rhs);
+  double f = sol.w ();
+  if (f > 1e-6 /*skip weird solutions*/) {
+    scale = 1.0 / f;
+    displacement = QVector3D (sol.x (), sol.y (), ztarget);
+  }
+}
+
+}
diff --git a/src/plugins/tools/view_25d/lay_plugin/layD25ViewUtils.h b/src/plugins/tools/view_25d/lay_plugin/layD25ViewUtils.h
new file mode 100644
index 000000000..b4bc140ea
--- /dev/null
+++ b/src/plugins/tools/view_25d/lay_plugin/layD25ViewUtils.h
@@ -0,0 +1,92 @@
+
+/*
+
+  KLayout Layout Viewer
+  Copyright (C) 2006-2020 Matthias Koefferlein
+
+  This program is free software; you can redistribute it and/or modify
+  it under the terms of the GNU General Public License as published by
+  the Free Software Foundation; either version 2 of the License, or
+  (at your option) any later version.
+
+  This program is distributed in the hope that it will be useful,
+  but WITHOUT ANY WARRANTY; without even the implied warranty of
+  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+  GNU General Public License for more details.
+
+  You should have received a copy of the GNU General Public License
+  along with this program; if not, write to the Free Software
+  Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
+
+*/
+
+#ifndef HDR_layD25ViewUtils
+#define HDR_layD25ViewUtils
+
+#include "layPluginCommon.h"
+
+#include <QVector3D>
+#include <QMatrix4x4>
+#include <algorithm>
+
+namespace lay
+{
+
+/**
+ *  @brief Computes the cutpoint between a line and a plane
+ *
+ *  The line is given by a point and a direction (line, line_dir).
+ *  The plane is given by a point and a normal vector (plane, plane_normal)
+ *  The "first" component of the returned pair is false if not hit is present.
+ */
+
+LAY_PLUGIN_PUBLIC std::pair<bool, QVector3D>
+cutpoint_line_with_plane (const QVector3D &line, const QVector3D &line_dir, const QVector3D &plane, const QVector3D &plane_normal);
+
+/**
+ *  @brief Computes the cutpoint between a line and a face
+ *
+ *  The line is given by a point and a direction (line, line_dir).
+ *  The face is given by a plane point and two vectors spanning the face.
+ *  The "first" component of the returned pair is false if not hit is present.
+ */
+
+LAY_PLUGIN_PUBLIC std::pair<bool, QVector3D>
+cutpoint_line_with_face (const QVector3D &line, const QVector3D &dir, const QVector3D &plane, const QVector3D &u, const QVector3D &v);
+
+/**
+ *  @brief Determines a good hit point of a view line and a cuboid
+ *
+ *  "corner, dim" are the coordinates for the cuboid (corner is the bottom, left, foremost corner, dim
+ *  is (width, height, depth)
+ *  "line, line_dir" is the view line where "line_dir" is pointing from the camera to the object.
+ *  The returned point is a suitable hit point.
+ *  The "first" component of the returned pair is false if no hit is present.
+ */
+LAY_PLUGIN_PUBLIC std::pair<bool, QVector3D>
+hit_point_with_cuboid (const QVector3D &line, const QVector3D &line_dir, const QVector3D &corner, const QVector3D &dim);
+
+/**
+ *  @brief For a given pixel coordinate and camera transformation matrix compute a line containing all points corresponding to this pixel
+ *
+ *  The returned pair contains a point and a direction vector describing the line.
+ */
+LAY_PLUGIN_PUBLIC std::pair<QVector3D, QVector3D>
+camera_normal (const QMatrix4x4 &camera_trans, double x, double y);
+
+/**
+ *  @brief Normalizes a scene transformation
+ *
+ *  Scene transformations consist of a scaling and displacement. Both are
+ *  interchangeable to some extent under the presence of a perspective
+ *  transformation (further away makes the scene smaller). This normalization
+ *  tries to find a displacement which has "ztarget" target value for z. Without normalization
+ *  the scene tends to "move away" with respect to z.
+ */
+LAY_PLUGIN_PUBLIC void
+normalize_scene_trans (const QMatrix4x4 &cam_trans, QVector3D &displacement, double &scale, double ztarget = 0.0);
+
+}
+
+#endif
+
diff --git a/src/plugins/tools/view_25d/lay_plugin/layD25ViewWidget.cc b/src/plugins/tools/view_25d/lay_plugin/layD25ViewWidget.cc
new file mode 100644
index 000000000..ff9fc8f2a
--- /dev/null
+++ b/src/plugins/tools/view_25d/lay_plugin/layD25ViewWidget.cc
@@ -0,0 +1,1119 @@
+
+/*
+
+  KLayout Layout Viewer
+  Copyright (C) 2006-2020 Matthias Koefferlein
+
+  This program is free software; you can redistribute it and/or modify
+  it under the terms of the GNU General Public License as published by
+  the Free Software Foundation; either version 2 of the License, or
+  (at your option) any later version.
+
+  This program is distributed in the hope that it will be useful,
+  but WITHOUT ANY WARRANTY; without even the implied warranty of
+  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+  GNU General Public License for more details.
+
+  You should have received a copy of the GNU General Public License
+  along with this program; if not, write to the Free Software
+  Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
+
+*/
+
+
+#include "layD25ViewWidget.h"
+#include "layD25ViewUtils.h"
+#include "layLayoutView.h"
+
+#include "dbRecursiveShapeIterator.h"
+#include "dbD25TechnologyComponent.h"
+#include "dbEdgeProcessor.h"
+#include "dbPolygonGenerators.h"
+#include "dbPolygonTools.h"
+
+#include "tlException.h"
+
+#include <QWheelEvent>
+#include <QMouseEvent>
+#include <QKeyEvent>
+
+#include "math.h"
+
+namespace lay
+{
+
+// ------------------------------------------------------------------------------
+
+D25InteractionMode::D25InteractionMode (D25ViewWidget *view)
+  : mp_view (view)
+{
+  //  .. nothing yet ..
+}
+
+D25InteractionMode::~D25InteractionMode ()
+{
+  //  .. nothing yet ..
+}
+
+
+// ------------------------------------------------------------------------------
+
+class D25PanInteractionMode
+  : public D25InteractionMode
+{
+public:
+  D25PanInteractionMode (D25ViewWidget *widget, const QPoint &pos)
+    : D25InteractionMode (widget), m_start_pos (pos)
+  {
+    m_start_displacement = widget->displacement ();
+
+    double px = (pos.x () - widget->width () / 2) * 2.0 / widget->width ();
+    double py = -(pos.y () - widget->height () / 2) * 2.0 / widget->height ();
+
+    //  compute vector of line of sight
+    std::pair<QVector3D, QVector3D> ray = camera_normal (view ()->cam_perspective () * view ()->cam_trans (), px, py);
+
+    //  by definition the ray goes through the camera position
+    QVector3D hp = widget->hit_point_with_scene (ray.second);
+
+    m_focus_dist = (widget->cam_position () - hp).length ();
+  }
+
+  virtual ~D25PanInteractionMode ()
+  {
+    //  .. nothing yet ..
+  }
+
+  virtual void mouse_move (QMouseEvent *event)
+  {
+    QPoint d = event->pos () - m_start_pos;
+    double f = tan ((view ()->cam_fov () / 2) / 180.0 * M_PI) * m_focus_dist * 2.0 / double (view ()->height ());
+    double dx = d.x () * f;
+    double dy = -d.y () * f;
+
+    QVector3D xv (cos (view ()->cam_azimuth () * M_PI / 180.0), 0.0, sin (view ()->cam_azimuth () * M_PI / 180.0));
+    double re = sin (view ()->cam_elevation () * M_PI / 180.0);
+    QVector3D yv (-re * xv.z (), cos (view ()->cam_elevation () * M_PI / 180.0), re * xv.x ());
+    QVector3D drag = xv * dx + yv * dy;
+
+    view ()->set_displacement (m_start_displacement + drag / view ()->scale_factor ());
+  }
+
+private:
+  QPoint m_start_pos;
+  double m_focus_dist;
+  QVector3D m_start_displacement;
+};
+
+// ------------------------------------------------------------------------------
+
+class D25Rotate2DInteractionMode
+  : public D25InteractionMode
+{
+public:
+  D25Rotate2DInteractionMode (D25ViewWidget *widget, const QPoint &pos)
+    : D25InteractionMode (widget), m_start_pos (pos)
+  {
+    m_start_cam_azimuth = widget->cam_azimuth ();
+    m_start_cam_elevation = widget->cam_elevation ();
+  }
+
+  virtual ~D25Rotate2DInteractionMode ()
+  {
+    //  .. nothing yet ..
+  }
+
+  virtual void mouse_move (QMouseEvent *event)
+  {
+    //  fixed focus point for rotation
+    double focus_dist = 2.0;
+
+    QPoint d = event->pos () - m_start_pos;
+    double f = tan ((view ()->cam_fov () / 2) / 180.0 * M_PI) * focus_dist * 2.0 / double (view ()->height ());
+    double dx = d.x () * f;
+    double dy = -d.y () * f;
+
+    double da = dx / (view ()->cam_dist () - focus_dist) * 180.0 / M_PI;
+    view ()->set_cam_azimuth (m_start_cam_azimuth + da);
+
+    double de = dy / (view ()->cam_dist () - focus_dist) * 180.0 / M_PI;
+    view ()->set_cam_elevation (m_start_cam_elevation + de);
+  }
+
+private:
+  QPoint m_start_pos;
+  double m_start_cam_azimuth, m_start_cam_elevation;
+};
+
+// ------------------------------------------------------------------------------
+
+class D25RotateAzimuthInteractionMode
+  : public D25InteractionMode
+{
+public:
+  D25RotateAzimuthInteractionMode (D25ViewWidget *widget, const QPoint &pos)
+    : D25InteractionMode (widget), m_start_pos (pos)
+  {
+    //  .. nothing yet ..
+  }
+
+  virtual ~D25RotateAzimuthInteractionMode ()
+  {
+    //  .. nothing yet ..
+  }
+
+  virtual void mouse_move (QMouseEvent *event)
+  {
+    //  simple change of azimuth only - with center in the middle
+
+    QPoint m = event->pos () - m_start_pos;
+    QVector3D p (m_start_pos.x () - view ()->width () / 2, -m_start_pos.y () + view ()->height () / 2, 0);
+    QVector3D d (m.x (), -m.y (), 0);
+
+    double cp = QVector3D::crossProduct (p, p + d).z () / p.length () / (p + d).length ();
+    cp = std::max (-1.0, std::min (1.0, cp));
+    double da = asin (cp) * 180.0 / M_PI;
+
+    view ()->set_cam_azimuth (view ()->cam_azimuth () + da);
+    m_start_pos = event->pos ();
+  }
+
+private:
+  QPoint m_start_pos;
+};
+
+// ------------------------------------------------------------------------------
+
+D25ViewWidget::D25ViewWidget (QWidget *parent)
+  : QOpenGLWidget (parent),
+    m_shapes_program (0)
+{
+  QSurfaceFormat format;
+  format.setDepthBufferSize (24);
+  format.setSamples (4); //  more -> widget extends beyond boundary!
+  format.setStencilBufferSize (8);
+  format.setProfile (QSurfaceFormat::CoreProfile);
+  setFormat (format);
+
+  m_zmin = m_zmax = 0.0;
+  mp_view = 0;
+}
+
+D25ViewWidget::~D25ViewWidget ()
+{
+  // Make sure the context is current and then explicitly
+  // destroy all underlying OpenGL resources.
+  makeCurrent ();
+
+  delete m_shapes_program;
+
+  doneCurrent ();
+}
+
+void
+D25ViewWidget::reset ()
+{
+  m_scale_factor = 1.0;
+  mp_mode.reset (0);
+
+  camera_reset ();
+}
+
+void
+D25ViewWidget::wheelEvent (QWheelEvent *event)
+{
+  if (event->angleDelta ().y () == 0) {
+    return;
+  }
+
+  double px = (event->pos ().x () - width () / 2) * 2.0 / width ();
+  double py = -(event->pos ().y () - height () / 2) * 2.0 / height ();
+
+  if (top_view ()) {
+
+    //  Plain zoom
+
+    QVector3D hp (px, py, 0.0);
+
+    double f = exp (event->angleDelta ().y () * (1.0 / (90 * 8)));
+
+    m_scale_factor *= f;
+    m_displacement += hp * (1.0 - f) / m_scale_factor;
+
+    emit scale_factor_changed (m_scale_factor);
+
+  } else {
+
+    //  compute vector of line of sight
+    std::pair<QVector3D, QVector3D> ray = camera_normal (cam_perspective () * cam_trans (), px, py);
+
+    //  by definition the ray goes through the camera position
+    QVector3D hp = hit_point_with_scene (ray.second);
+
+    if (! (event->modifiers () & Qt::ControlModifier)) {
+
+      //  No Ctrl is closeup
+
+      double f = event->angleDelta ().y () * (1.0 / (90 * 8));
+      m_displacement += -((f / m_scale_factor) * std::min (cam_dist (), double ((cam_position () - hp).length ()))) * ray.second;
+
+    } else {
+
+      //  "Ctrl" is zoom
+
+      double f = exp (event->angleDelta ().y () * (1.0 / (90 * 8)));
+
+      QVector3D initial_displacement = m_displacement;
+      QVector3D displacement = m_displacement;
+
+      m_scale_factor *= f;
+      displacement += hp * (1.0 - f) / m_scale_factor;
+
+      //  normalize the scene translation so the scene does not "flee"
+
+      QMatrix4x4 ct = cam_trans ();
+      initial_displacement = ct.map (initial_displacement);
+      displacement = ct.map (displacement);
+
+      lay::normalize_scene_trans (cam_perspective (), displacement, m_scale_factor, initial_displacement.z ());
+
+      m_displacement = ct.inverted ().map (displacement);
+
+      emit scale_factor_changed (m_scale_factor);
+
+    }
+
+  }
+
+  refresh ();
+}
+
+void
+D25ViewWidget::keyPressEvent (QKeyEvent *event)
+{
+  if (event->key () == Qt::Key_Shift) {
+    mp_mode.reset (0);
+    set_top_view (true);
+  }
+}
+
+void
+D25ViewWidget::keyReleaseEvent (QKeyEvent *event)
+{
+  if (event->key () == Qt::Key_Shift) {
+    mp_mode.reset (0);
+    set_top_view (false);
+  }
+}
+
+QVector3D
+D25ViewWidget::hit_point_with_scene (const QVector3D &line_dir)
+{
+  double min_focus_dist = 0.5;
+
+  QVector3D corner = (QVector3D (m_bbox.left (), m_zmin, -(m_bbox.bottom () + m_bbox.height ())) + m_displacement) * m_scale_factor;
+  QVector3D dim = QVector3D (m_bbox.width (), m_zmax - m_zmin, m_bbox.height ()) * m_scale_factor;
+  QVector3D line = cam_position ();
+
+  std::pair<bool, QVector3D> hp = lay::hit_point_with_cuboid (line, line_dir, corner, dim);
+  if (! hp.first) {
+    return line + line_dir * min_focus_dist;
+  } else if (QVector3D::dotProduct (line_dir, hp.second - line) < min_focus_dist) {
+    //  limit to min focus distance (not behind)
+    return line + line_dir * min_focus_dist;
+  } else {
+    return hp.second;
+  }
+}
+
+void
+D25ViewWidget::mousePressEvent (QMouseEvent *event)
+{
+  mp_mode.reset (0);
+
+  if (event->button () == Qt::MidButton) {
+    mp_mode.reset (new D25PanInteractionMode (this, event->pos ()));
+  } else if (event->button () == Qt::LeftButton) {
+    if (! top_view ()) {
+      mp_mode.reset (new D25Rotate2DInteractionMode (this, event->pos ()));
+    } else {
+      mp_mode.reset (new D25RotateAzimuthInteractionMode (this, event->pos ()));
+    }
+  }
+}
+
+void
+D25ViewWidget::mouseReleaseEvent (QMouseEvent * /*event*/)
+{
+  mp_mode.reset (0);
+}
+
+void
+D25ViewWidget::mouseMoveEvent (QMouseEvent *event)
+{
+  if (mp_mode.get ()) {
+    mp_mode->mouse_move (event);
+  }
+}
+
+inline double square (double x) { return x * x; }
+
+void
+D25ViewWidget::fit ()
+{
+  //  we pick a scale factor to adjust the z dimension roughly to 1/4 of the screen height at a focus distance of 2
+  double norm_height = 0.5;
+  double in_focus = 2.0;
+  m_scale_factor = (tan (cam_fov () * M_PI / 180.0 / 2.0) * 2.0) * in_focus * norm_height / std::max (0.001, (m_zmax - m_zmin));
+
+  QVector3D dim = QVector3D (m_bbox.width (), m_zmax - m_zmin, m_bbox.height ()) * m_scale_factor;
+  QVector3D bll = QVector3D (m_bbox.left (), m_zmin, -(m_bbox.bottom () + m_bbox.height ()));
+
+  //  now we pick a displacement which moves the center to y = 0 and x, y in a way that the dimension covers the field of
+  //  view and is centered.
+  //  (we use the elliptic approximation which works exactly for azimuth angles which are a multiple of 90 degree)
+
+  double dh = sqrt (square (cos (cam_azimuth () * M_PI / 180.0) * dim.x ()) + square (sin (cam_azimuth () * M_PI / 180.0) * dim.z ()));
+  double dv = sqrt (square (cos (cam_azimuth () * M_PI / 180.0) * dim.z ()) + square (sin (cam_azimuth () * M_PI / 180.0) * dim.x ()));
+
+  double d = std::max (dh, fabs (sin (cam_elevation ()) * dv));
+
+  QVector3D new_center (0.0, 0.0, -dv / 2.0 + std::max (0.0, -d / (2.0 * tan (cam_fov () * M_PI / 180.0 / 2.0)) + cam_dist ()));
+  QVector3D new_center_in_scene = cam_trans ().inverted ().map (new_center);
+
+  new_center_in_scene.setY (0.0);
+
+  m_displacement = (new_center_in_scene - dim * 0.5) / m_scale_factor - bll;
+
+  refresh ();
+
+  emit scale_factor_changed (m_scale_factor);
+}
+
+void
+D25ViewWidget::refresh ()
+{
+  update ();
+}
+
+void
+D25ViewWidget::camera_changed ()
+{
+  refresh ();
+}
+
+double
+D25ViewWidget::aspect_ratio () const
+{
+  return double (width ()) / double (height ());
+}
+
+bool
+D25ViewWidget::attach_view (LayoutView *view)
+{
+  bool any = false;
+
+  if (mp_view != view) {
+
+    mp_view = view;
+
+    any = prepare_view ();
+    reset ();
+
+  }
+
+  return any;
+}
+
+namespace {
+
+  class ZDataCache
+  {
+  public:
+    ZDataCache () { }
+
+    const db::D25LayerInfo *operator() (lay::LayoutView *view, int cv_index, int layer_index)
+    {
+      std::map<int, std::map<int, const db::D25LayerInfo *> >::const_iterator c = m_cache.find (cv_index);
+      if (c != m_cache.end ()) {
+        std::map<int, const db::D25LayerInfo *>::const_iterator l = c->second.find (layer_index);
+        if (l != c->second.end ()) {
+          return l->second;
+        } else {
+          return 0;
+        }
+      }
+
+      std::map<int, const db::D25LayerInfo *> &lcache = m_cache [cv_index];
+
+      const db::D25TechnologyComponent *comp = 0;
+
+      const lay::CellView &cv = view->cellview (cv_index);
+      if (cv.is_valid () && cv->technology ()) {
+        const db::Technology *tech = cv->technology ();
+        comp = dynamic_cast<const db::D25TechnologyComponent *> (tech->component_by_name ("d25"));
+      }
+
+      if (comp) {
+
+        std::map<db::LayerProperties, const db::D25LayerInfo *, db::LPLogicalLessFunc> zi_by_lp;
+        for (db::D25TechnologyComponent::const_iterator i = comp->begin (); i != comp->end (); ++i) {
+          zi_by_lp.insert (std::make_pair (i->layer (), i.operator-> ()));
+        }
+
+        const db::Layout &ly = cv->layout ();
+        for (int l = 0; l < int (ly.layers ()); ++l) {
+          if (ly.is_valid_layer (l)) {
+            const db::LayerProperties &lp = ly.get_properties (l);
+            std::map<db::LayerProperties, const db::D25LayerInfo *, db::LPLogicalLessFunc>::const_iterator z = zi_by_lp.find (lp);
+            if (z == zi_by_lp.end () && ! lp.name.empty ()) {
+              //  If possible, try by name only
+              z = zi_by_lp.find (db::LayerProperties (lp.name));
+            }
+            if (z != zi_by_lp.end ()) {
+              lcache[l] = z->second;
+            }
+          }
+        }
+
+      }
+
+      return operator() (view, cv_index, layer_index);
+
+    }
+
+
+  private:
+    std::map<int, std::map<int, const db::D25LayerInfo *> > m_cache;
+  };
+
+}
+
+bool
+D25ViewWidget::prepare_view ()
+{
+  m_layers.clear ();
+  m_vertex_chunks.clear ();
+
+  m_bbox = db::DBox ();
+  bool zset = false;
+  m_zmin = m_zmax = 0.0;
+
+  if (! mp_view) {
+    m_bbox = db::DBox (-1.0, -1.0, 1.0, 1.0);
+    return false;
+  }
+
+  ZDataCache zdata;
+  bool any = false;
+
+  for (lay::LayerPropertiesConstIterator lp = mp_view->begin_layers (); ! lp.at_end (); ++lp) {
+
+    const db::D25LayerInfo *zi = 0;
+    if (! lp->has_children () && lp->visible (true)) {
+      zi = zdata (mp_view, lp->cellview_index (), lp->layer_index ());
+    }
+
+    if (zi) {
+
+      any = true;
+
+      double z0 = zi->zstart ();
+      double z1 = zi->zstop ();
+
+      lay::color_t color = lp->fill_color (true);
+
+      m_vertex_chunks.push_back (chunks_type ());
+
+      LayerInfo info;
+      info.color[0] = ((color >> 16) & 0xff) / 255.0f;
+      info.color[1] = ((color >> 8) & 0xff) / 255.0f;
+      info.color[2] = (color & 0xff) / 255.0f;
+      info.vertex_chunk = &m_vertex_chunks.back ();
+
+      m_layers.push_back (info);
+
+      const lay::CellView &cv = mp_view->cellview ((unsigned int) lp->cellview_index ());
+      render_layout (m_vertex_chunks.back (), cv->layout (), *cv.cell (), (unsigned int) lp->layer_index (), z0, z1);
+
+      m_bbox += db::DBox (cv.cell ()->bbox ((unsigned int) lp->layer_index ())) * cv->layout ().dbu ();
+
+      if (! zset) {
+        m_zmin = z0;
+        m_zmax = z1;
+        zset = true;
+      } else {
+        m_zmin = std::min (z0, m_zmin);
+        m_zmax = std::max (z1, m_zmax);
+      }
+
+    }
+
+  }
+
+  return any;
+}
+
+void
+D25ViewWidget::render_polygon (D25ViewWidget::chunks_type &chunks, const db::Polygon &poly, double dbu, double zstart, double zstop)
+{
+  if (poly.hull ().size () > 4) {
+
+    std::vector<db::Polygon> poly_heap;
+
+    db::split_polygon (poly, poly_heap);
+    for (std::vector<db::Polygon>::const_iterator p = poly_heap.begin (); p != poly_heap.end (); ++p) {
+      render_polygon (chunks, *p, dbu, zstart, zstop);
+    }
+
+  } else if (poly.hull ().size () >= 3) {
+
+    db::Point pts [4];
+    std::copy (poly.hull ().begin (), poly.hull ().end (), &pts [0]);
+
+    //  triangle bottom
+
+    chunks.add (pts[0].x () * dbu, zstart, pts[0].y () * dbu);
+    chunks.add (pts[2].x () * dbu, zstart, pts[2].y () * dbu);
+    chunks.add (pts[1].x () * dbu, zstart, pts[1].y () * dbu);
+
+    //  triangle top
+    chunks.add (pts[0].x () * dbu, zstop, pts[0].y () * dbu);
+    chunks.add (pts[1].x () * dbu, zstop, pts[1].y () * dbu);
+    chunks.add (pts[2].x () * dbu, zstop, pts[2].y () * dbu);
+
+    if (poly.hull ().size () == 4) {
+
+      //  triangle bottom
+      chunks.add (pts[0].x () * dbu, zstart, pts[0].y () * dbu);
+      chunks.add (pts[3].x () * dbu, zstart, pts[3].y () * dbu);
+      chunks.add (pts[2].x () * dbu, zstart, pts[2].y () * dbu);
+
+      //  triangle top
+      chunks.add (pts[0].x () * dbu, zstop, pts[0].y () * dbu);
+      chunks.add (pts[2].x () * dbu, zstop, pts[2].y () * dbu);
+      chunks.add (pts[3].x () * dbu, zstop, pts[3].y () * dbu);
+
+    }
+
+  }
+}
+
+void
+D25ViewWidget::render_wall (D25ViewWidget::chunks_type &chunks, const db::Edge &edge, double dbu, double zstart, double zstop)
+{
+  chunks.add (edge.p1 ().x () * dbu, zstart, edge.p1 ().y () * dbu);
+  chunks.add (edge.p2 ().x () * dbu, zstop, edge.p2 ().y () * dbu);
+  chunks.add (edge.p1 ().x () * dbu, zstop, edge.p1 ().y () * dbu);
+  chunks.add (edge.p1 ().x () * dbu, zstart, edge.p1 ().y () * dbu);
+  chunks.add (edge.p2 ().x () * dbu, zstart, edge.p2 ().y () * dbu);
+  chunks.add (edge.p2 ().x () * dbu, zstop, edge.p2 ().y () * dbu);
+}
+
+void
+D25ViewWidget::render_layout (D25ViewWidget::chunks_type &chunks, const db::Layout &layout, const db::Cell &cell, unsigned int layer, double zstart, double zstop)
+{
+  db::EdgeProcessor ep;
+  std::vector<db::Polygon> poly_heap;
+
+  //  TODO: hidden cells, hierarchy depth ...
+  db::RecursiveShapeIterator s (layout, cell, layer);
+  s.shape_flags (db::ShapeIterator::Polygons | db::ShapeIterator::Paths | db::ShapeIterator::Boxes);
+  for ( ; ! s.at_end (); ++s) {
+
+    db::Polygon polygon;
+    s->polygon (polygon);
+    polygon.transform (s.trans ());
+
+    if (polygon.holes () == 0 && polygon.hull ().size () <= 4) {
+
+      render_polygon (chunks, polygon, layout.dbu (), zstart, zstop);
+
+      for (db::Polygon::polygon_edge_iterator e = polygon.begin_edge (); ! e.at_end (); ++e) {
+        render_wall (chunks, *e, layout.dbu (), zstart, zstop);
+      }
+
+    } else {
+
+      poly_heap.clear ();
+      ep.clear ();
+
+      ep.insert_sequence (polygon.begin_edge ());
+      {
+        db::PolygonContainer pc (poly_heap);
+        db::PolygonGenerator out (pc, true /*resolve holes*/, false /*min coherence for splitting*/);
+        db::SimpleMerge op;
+        ep.process (out, op);
+      }
+
+      for (std::vector<db::Polygon>::const_iterator p = poly_heap.begin (); p != poly_heap.end (); ++p) {
+        render_polygon (chunks, *p, layout.dbu (), zstart, zstop);
+      }
+
+      poly_heap.clear ();
+      ep.clear ();
+
+      ep.insert_sequence (polygon.begin_edge ());
+      {
+        db::PolygonContainer pc (poly_heap);
+        db::PolygonGenerator out (pc, false /*don't resolve holes*/, false /*min coherence for splitting*/);
+        db::SimpleMerge op;
+        ep.process (out, op);
+      }
+
+      for (std::vector<db::Polygon>::const_iterator p = poly_heap.begin (); p != poly_heap.end (); ++p) {
+        for (db::Polygon::polygon_edge_iterator e = p->begin_edge (); ! e.at_end (); ++e) {
+          render_wall (chunks, *e, layout.dbu (), zstart, zstop);
+        }
+      }
+
+    }
+
+  }
+}
+
+static std::pair<double, double> find_grid (double v)
+{
+  for (int p = -12; p < 12; ++p) {
+    double g10 = pow (10, double (p));
+    if (v > 100 * g10) {
+      continue;
+    } else if (v < 10 * g10) {
+      return std::make_pair (g10, g10);
+    } else if (v < 20 * g10) {
+      return std::make_pair (g10, g10 * 0.1);
+    } else if (v < 50 * g10) {
+      return std::make_pair (2.0 * g10, g10);
+    } else {
+      return std::make_pair (5.0 * g10, g10);
+    }
+  }
+
+  return std::make_pair (v, v);
+}
+
+void
+D25ViewWidget::initializeGL ()
+{
+  QOpenGLFunctions::initializeOpenGLFunctions();
+
+  glEnable (GL_BLEND);
+  glBlendFunc (GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);
+
+  static const char *shapes_vertex_shader_source =
+      "#version 320 es\n"
+      "#undef lowp\n"
+      "#undef highp\n"
+      "#undef mediump\n"
+      "layout (location = 0) in vec4 posAttr;\n"
+      "\n"
+      "void main() {\n"
+      "   gl_Position = posAttr;\n"
+      "}\n";
+
+  static const char *shapes_geometry_shader_source =
+      "#version 320 es\n"
+      "#undef lowp\n"
+      "#undef highp\n"
+      "#undef mediump\n"
+      "\n"
+      "uniform vec4 color;\n"
+      "uniform vec4 ambient;\n"
+      "uniform vec3 illum;\n"
+      "out lowp vec4 vertexColor;\n"
+      "uniform mat4 matrix;\n"
+      "layout (triangles) in;\n"
+      "layout (triangle_strip, max_vertices = 3) out;\n"
+      "\n"
+      "void main() {\n"
+      "   vec4 p0 = gl_in[0].gl_Position;\n"
+      "   vec4 p1 = gl_in[1].gl_Position;\n"
+      "   vec4 p2 = gl_in[2].gl_Position;\n"
+      "   vec3 n = cross(p2.xyz - p0.xyz, p1.xyz - p0.xyz);\n"
+      "   float dp = dot(normalize(n), illum);\n"
+      "   vertexColor = color * (dp * 0.5 + 0.5) - (min(0.0, dp) * ambient);\n"
+      "   vertexColor.a = 1.0;\n"
+      "   gl_Position = matrix * p0;\n"
+      "   EmitVertex();\n"
+      "   gl_Position = matrix * p1;\n"
+      "   EmitVertex();\n"
+      "   gl_Position = matrix * p2;\n"
+      "   EmitVertex();\n"
+      "   EndPrimitive();\n"
+      "}\n";
+
+  static const char *shapes_fragment_shader_source =
+      "#version 320 es\n"
+      "#undef lowp\n"
+      "#undef highp\n"
+      "#undef mediump\n"
+      "in lowp vec4 vertexColor;\n"
+      "out lowp vec4 fragColor;\n"
+      "uniform highp float mist_factor;\n"
+      "uniform highp float mist_add;\n"
+      "\n"
+      "lowp vec4 color_by_z(lowp vec4 c, highp float z) {\n"
+      "  highp float mist_rgb = c.g * mist_factor + mist_add;\n"
+      "  lowp vec4 mist_color = vec4(mist_rgb, mist_rgb, mist_rgb, 1.0);\n"
+      "  highp float d = 0.12;\n" //  d + dd/2 = 0.15 = 1/?
+      "  highp float dd = 0.06;\n"
+      "  highp float f = 1.0;\n"
+      "  if (z < d - dd) {\n"
+      "    f = 0.0;\n"
+      "  } else if (z < d + dd) {\n"
+      "    f = (z - (d - dd)) / (2.0 * dd);\n"
+      "  }\n"
+      "  return (1.0 - f) * mist_color + f * c;\n"
+      "};\n"
+      "\n"
+      "void main() {\n"
+      "   fragColor = color_by_z(vertexColor, gl_FragCoord.w);\n"
+      "}\n";
+
+  m_shapes_program = new QOpenGLShaderProgram (this);
+  if (! m_shapes_program->addShaderFromSourceCode (QOpenGLShader::Vertex, shapes_vertex_shader_source)) {
+    throw tl::Exception (std::string ("Shapes vertex shader compilation failed:\n") + tl::to_string (m_shapes_program->log ()));
+  }
+  if (! m_shapes_program->addShaderFromSourceCode (QOpenGLShader::Geometry, shapes_geometry_shader_source)) {
+    throw tl::Exception (std::string ("Shapes geometry shader compilation failed:\n") + tl::to_string (m_shapes_program->log ()));
+  }
+  if (! m_shapes_program->addShaderFromSourceCode (QOpenGLShader::Fragment, shapes_fragment_shader_source)) {
+    throw tl::Exception (std::string ("Shapes fragment shader compilation failed:\n") + tl::to_string (m_shapes_program->log ()));
+  }
+  if (! m_shapes_program->link ()) {
+    throw tl::Exception (std::string ("Shapes shader program linking failed failed:\n") + tl::to_string (m_shapes_program->log ()));
+  }
+
+  //  grid plane shader source
+
+  static const char *gridplan_vertex_shader_source =
+      "#version 320 es\n"
+      "#undef lowp\n"
+      "#undef highp\n"
+      "#undef mediump\n"
+      "layout (location = 0) in vec4 posAttr;\n"
+      "uniform mat4 matrix;\n"
+      "\n"
+      "void main() {\n"
+      "   gl_Position = matrix * posAttr;\n"
+      "}\n";
+
+  static const char *gridplan_fragment_shader_source =
+      "#version 320 es\n"
+      "#undef lowp\n"
+      "#undef highp\n"
+      "#undef mediump\n"
+      "uniform lowp vec4 color;\n"
+      "out lowp vec4 fragColor;\n"
+      "void main() {\n"
+      "   fragColor = color;\n"
+      "}\n";
+
+  m_gridplane_program = new QOpenGLShaderProgram (this);
+  if (! m_gridplane_program->addShaderFromSourceCode (QOpenGLShader::Vertex, gridplan_vertex_shader_source)) {
+    throw tl::Exception (std::string ("Grid plane vertex shader compilation failed:\n") + tl::to_string (m_gridplane_program->log ()));
+  }
+  if (! m_gridplane_program->addShaderFromSourceCode (QOpenGLShader::Fragment, gridplan_fragment_shader_source)) {
+    throw tl::Exception (std::string ("Grid plane fragment shader compilation failed:\n") + tl::to_string (m_gridplane_program->log ()));
+  }
+  if (! m_gridplane_program->link ()) {
+    throw tl::Exception (std::string ("Grid plane shader program linking failed:\n") + tl::to_string (m_gridplane_program->log ()));
+  }
+}
+
+void
+D25ViewWidget::paintGL ()
+{
+  const qreal retinaScale = devicePixelRatio ();
+  glViewport (0, 0, width () * retinaScale, height () * retinaScale);
+
+  QColor c = mp_view->background_color ();
+  float foreground_rgb = (c.green () > 128 ? 0.0f : 1.0f);
+  float ambient = (c.green () > 128 ? 0.8f : 0.25f);
+  float mist_factor = (c.green () > 128 ? 0.2f : 0.4f);
+  float mist_add = (c.green () > 128 ? 0.8f : 0.2f);
+  glClearColor (float (c.red ()) / 255.0f, float (c.green ()) / 255.0f, float (c.blue ()) / 255.0f, 1.0);
+  glClear (GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
+
+  QMatrix4x4 scene_trans, scene_trans_wo_y;
+
+  //  provide the displacement and scaling (in this order!)
+  scene_trans.scale (m_scale_factor);
+  scene_trans.translate (m_displacement);
+  //  this way we can use y as z coordinate when drawing
+  scene_trans.scale (1.0, 1.0, -1.0);
+
+  scene_trans_wo_y = scene_trans;
+  scene_trans_wo_y.translate (QVector3D (0.0, -m_displacement.y (), 0.0));
+
+  const int positions = 0;
+
+  m_shapes_program->bind ();
+
+  //  draw the actual layout
+
+  m_shapes_program->setUniformValue ("matrix", cam_perspective () * cam_trans () * scene_trans);
+
+  //  NOTE: z axis of illum points towards the scene because we include the z inversion in the scene transformation matrix
+  m_shapes_program->setUniformValue ("illum", QVector3D (-3.0, -4.0, 2.0).normalized ());
+
+  m_shapes_program->setUniformValue ("ambient", QVector4D (ambient, ambient, ambient, 1.0));
+  m_shapes_program->setUniformValue ("mist_factor", mist_factor);
+  m_shapes_program->setUniformValue ("mist_add", mist_add);
+
+  glEnable (GL_DEPTH_TEST);
+  glEnableVertexAttribArray (positions);
+
+  for (std::list<LayerInfo>::const_iterator l = m_layers.begin (); l != m_layers.end (); ++l) {
+    m_shapes_program->setUniformValue ("color", l->color [0], l->color [1], l->color [2], l->color [3]);
+    l->vertex_chunk->draw_to (this, positions, GL_TRIANGLES);
+  }
+
+  glDisableVertexAttribArray (positions);
+
+  m_shapes_program->release ();
+
+  //  decoration
+
+  //  a vertex buffer for the decoration
+  lay::mem_chunks<float, 1024 * 18> vertexes;
+
+  m_gridplane_program->bind ();
+
+  glEnable (GL_DEPTH_TEST);
+  glEnableVertexAttribArray (positions);
+
+  //  draw pivot compass
+
+  m_gridplane_program->setUniformValue ("matrix", cam_perspective () * cam_trans ());
+
+  double compass_rad = 0.3;
+  double compass_bars = 0.4;
+
+  vertexes.add (-compass_bars, 0.0, 0.0);
+  vertexes.add (compass_bars, 0.0, 0.0);
+
+  vertexes.add (0.0, 0.0, -compass_bars);
+  vertexes.add (0.0, 0.0, compass_bars);
+
+  int ncircle = 64;
+  double x = compass_rad, z = 0.0;
+  double da = 1.0 / double (ncircle) * M_PI * 2.0;
+
+  for (int i = 0; i < ncircle; ++i) {
+
+    double a = double (i + 1) * da;
+    double xx = compass_rad * cos (a);
+    double zz = compass_rad * sin (a);
+
+    vertexes.add (x, 0.0, z);
+    vertexes.add (xx, 0.0, zz);
+
+    x = xx;
+    z = zz;
+
+  }
+
+  m_gridplane_program->setUniformValue ("color", foreground_rgb, foreground_rgb, foreground_rgb, 0.25f);
+
+  glLineWidth (2.0);
+  vertexes.draw_to (this, positions, GL_LINES);
+
+  //  arrow
+
+  vertexes.clear ();
+
+  vertexes.add (-0.25 * compass_rad, 0.0, 0.6 * compass_rad);
+  vertexes.add (0.0, 0.0, -0.8 * compass_rad);
+  vertexes.add (0.25 * compass_rad, 0.0, 0.6 * compass_rad);
+
+  vertexes.draw_to (this, positions, GL_TRIANGLES);
+
+  //  draw base plane
+
+  m_gridplane_program->setUniformValue ("matrix", cam_perspective () * cam_trans () * scene_trans_wo_y);
+
+  std::pair<double, double> gg = find_grid (std::max (m_bbox.width (), m_bbox.height ()));
+  double gminor = gg.second, gmajor = gg.first;
+
+  double margin = std::max (m_bbox.width (), m_bbox.height ()) * 0.02;
+
+  double l = m_bbox.left ();
+  double r = m_bbox.right ();
+  double b = m_bbox.bottom ();
+  double t = m_bbox.top ();
+
+  //  major and minor grid lines
+
+  vertexes.clear ();
+
+  const double epsilon = 1e-6;
+
+  for (int major = 0; major < 2; ++major) {
+
+    m_gridplane_program->setUniformValue ("color", foreground_rgb, foreground_rgb, foreground_rgb, major ? 0.25f : 0.15f);
+
+    double x, y;
+    double step = (major ? gmajor : gminor);
+
+    x = ceil (l / step) * step;
+    for ( ; x < r - step * epsilon; x += step) {
+      if ((fabs (floor (x / gmajor + 0.5) * gmajor - x) < epsilon) == (major != 0)) {
+        vertexes.add (x, 0.0, b - margin);
+        vertexes.add (x, 0.0, t + margin);
+      }
+    }
+
+    y = ceil (b / step) * step;
+    for ( ; y < t - step * epsilon; y += step) {
+      if ((fabs (floor (y / gmajor + 0.5) * gmajor - y) < epsilon) == (major != 0)) {
+        vertexes.add (l - margin, 0.0, y);
+        vertexes.add (r + margin, 0.0, y);
+      }
+    }
+
+    glLineWidth (2.0);
+    vertexes.draw_to (this, positions, GL_LINES);
+
+  }
+
+  //  the plane itself
+
+  vertexes.clear ();
+
+  vertexes.add (l, 0.0, b);
+  vertexes.add (l, 0.0, t);
+  vertexes.add (r, 0.0, t);
+
+  vertexes.add (l, 0.0, b);
+  vertexes.add (r, 0.0, b);
+  vertexes.add (r, 0.0, t);
+
+  m_gridplane_program->setUniformValue ("color", foreground_rgb, foreground_rgb, foreground_rgb, 0.1f);
+
+  vertexes.draw_to (this, positions, GL_TRIANGLES);
+
+  //  the orientation cube
+
+  if (! top_view ()) {
+
+    glDisable (GL_DEPTH_TEST);
+
+    int cube_size = 64;
+    int cube_margin = 20;
+
+    QMatrix4x4 into_top_right_corner;
+    into_top_right_corner.translate (1.0 - 2.0 / width () * (cube_margin + cube_size / 2), 1.0 - 2.0 / height () * (cube_margin + cube_size / 2));
+    // into_top_right_corner.translate (0.5, 0.5, 0.0);
+    into_top_right_corner.scale (2.0 * cube_size / double (height ()), 2.0 * cube_size / double (height ()), 1.0);
+
+    m_gridplane_program->setUniformValue ("matrix", into_top_right_corner * cam_perspective () * cam_trans ());
+
+    vertexes.clear ();
+
+    vertexes.add (-1.0, -1.0, 1.0);
+    vertexes.add (-1.0, -1.0, -1.0);
+
+    vertexes.add (-1.0, 1.0, 1.0);
+    vertexes.add (-1.0, 1.0, -1.0);
+
+    vertexes.add (1.0, -1.0, 1.0);
+    vertexes.add (1.0, -1.0, -1.0);
+
+    vertexes.add (1.0, 1.0, 1.0);
+    vertexes.add (1.0, 1.0, -1.0);
+
+    vertexes.add (-1.0, -1.0, 1.0);
+    vertexes.add (-1.0, 1.0, 1.0);
+
+    vertexes.add (1.0, -1.0, 1.0);
+    vertexes.add (1.0, 1.0, 1.0);
+
+    vertexes.add (-1.0, -1.0, 1.0);
+    vertexes.add (1.0, -1.0, 1.0);
+
+    vertexes.add (-1.0, 1.0, 1.0);
+    vertexes.add (1.0, 1.0, 1.0);
+
+    vertexes.add (-1.0, -1.0, -1.0);
+    vertexes.add (-1.0, 1.0, -1.0);
+
+    vertexes.add (1.0, -1.0, -1.0);
+    vertexes.add (1.0, 1.0, -1.0);
+
+    vertexes.add (-1.0, -1.0, -1.0);
+    vertexes.add (1.0, -1.0, -1.0);
+
+    vertexes.add (-1.0, 1.0, -1.0);
+    vertexes.add (1.0, 1.0, -1.0);
+
+    m_gridplane_program->setUniformValue ("color", foreground_rgb, foreground_rgb, foreground_rgb, 0.2f);
+
+    vertexes.draw_to (this, positions, GL_LINES);
+
+    vertexes.clear ();
+
+    //  A "K" at the front
+    vertexes.add (-0.8, -0.8, 1.0);
+    vertexes.add (-0.8, 0.8, 1.0);
+    vertexes.add (-0.2, 0.8, 1.0);
+
+    vertexes.add (-0.8, -0.8, 1.0);
+    vertexes.add (-0.2, -0.8, 1.0);
+    vertexes.add (-0.2, 0.8, 1.0);
+
+    vertexes.add (0.2, 0.8, 1.0);
+    vertexes.add (0.8, 0.8, 1.0);
+    vertexes.add (0.8, 0.6, 1.0);
+
+    vertexes.add (0.2, 0.8, 1.0);
+    vertexes.add (0.8, 0.6, 1.0);
+    vertexes.add (0.6, 0.4, 1.0);
+
+    vertexes.add (-0.2, 0.4, 1.0);
+    vertexes.add (0.2, 0.8, 1.0);
+    vertexes.add (0.6, 0.4, 1.0);
+
+    vertexes.add (-0.2, 0.4, 1.0);
+    vertexes.add (0.6, 0.4, 1.0);
+    vertexes.add (0.2, 0.0, 1.0);
+
+    vertexes.add (-0.2, 0.4, 1.0);
+    vertexes.add (0.2, 0.0, 1.0);
+    vertexes.add (-0.2, -0.4, 1.0);
+
+    vertexes.add (-0.2, -0.4, 1.0);
+    vertexes.add (0.6, -0.4, 1.0);
+    vertexes.add (0.2, -0.0, 1.0);
+
+    vertexes.add (-0.2, -0.4, 1.0);
+    vertexes.add (0.2, -0.8, 1.0);
+    vertexes.add (0.6, -0.4, 1.0);
+
+    vertexes.add (0.2, -0.8, 1.0);
+    vertexes.add (0.8, -0.6, 1.0);
+    vertexes.add (0.6, -0.4, 1.0);
+
+    vertexes.add (0.2, -0.8, 1.0);
+    vertexes.add (0.8, -0.8, 1.0);
+    vertexes.add (0.8, -0.6, 1.0);
+
+    m_gridplane_program->setUniformValue ("color", foreground_rgb, foreground_rgb, foreground_rgb, 0.3f);
+
+    vertexes.draw_to (this, positions, GL_TRIANGLES);
+
+  }
+
+  glDisableVertexAttribArray (positions);
+
+  m_shapes_program->release ();
+}
+
+void
+D25ViewWidget::resizeGL (int /*w*/, int /*h*/)
+{
+  refresh ();
+}
+
+}
+
diff --git a/src/plugins/tools/view_25d/lay_plugin/layD25ViewWidget.h b/src/plugins/tools/view_25d/lay_plugin/layD25ViewWidget.h
new file mode 100644
index 000000000..e23b068a5
--- /dev/null
+++ b/src/plugins/tools/view_25d/lay_plugin/layD25ViewWidget.h
@@ -0,0 +1,150 @@
+
+/*
+
+  KLayout Layout Viewer
+  Copyright (C) 2006-2020 Matthias Koefferlein
+
+  This program is free software; you can redistribute it and/or modify
+  it under the terms of the GNU General Public License as published by
+  the Free Software Foundation; either version 2 of the License, or
+  (at your option) any later version.
+
+  This program is distributed in the hope that it will be useful,
+  but WITHOUT ANY WARRANTY; without even the implied warranty of
+  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+  GNU General Public License for more details.
+
+  You should have received a copy of the GNU General Public License
+  along with this program; if not, write to the Free Software
+  Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
+
+*/
+
+#ifndef HDR_layD25ViewWidget
+#define HDR_layD25ViewWidget
+
+#include "dbPolygon.h"
+
+#include "layD25MemChunks.h"
+#include "layD25Camera.h"
+
+#include <QOpenGLWidget>
+#include <QOpenGLVertexArrayObject>
+#include <QOpenGLBuffer>
+#include <QOpenGLShaderProgram>
+#include <QOpenGLFunctions>
+#include <QMatrix4x4>
+#include <QPoint>
+#include <QVector3D>
+
+#include <memory>
+
+namespace db
+{
+  class Layout;
+  class Cell;
+}
+
+namespace lay
+{
+
+class LayoutView;
+class D25ViewWidget;
+
+class D25InteractionMode
+{
+public:
+  D25InteractionMode (D25ViewWidget *widget);
+  virtual ~D25InteractionMode ();
+
+  D25ViewWidget *view () { return mp_view; }
+  virtual void mouse_move (QMouseEvent *event) = 0;
+
+private:
+  D25ViewWidget *mp_view;
+};
+
+class D25ViewWidget
+  : public QOpenGLWidget,
+    private QOpenGLFunctions,
+    public D25Camera
+{
+Q_OBJECT 
+
+public:
+  D25ViewWidget (QWidget *parent);
+  ~D25ViewWidget ();
+
+  void keyPressEvent (QKeyEvent *event);
+  void keyReleaseEvent (QKeyEvent *event);
+  void wheelEvent (QWheelEvent *event);
+  void mousePressEvent (QMouseEvent *event);
+  void mouseReleaseEvent (QMouseEvent *event);
+  void mouseMoveEvent (QMouseEvent *event);
+
+  bool attach_view(lay::LayoutView *view);
+
+  QVector3D hit_point_with_scene(const QVector3D &line_dir);
+  void refresh ();
+  void reset ();
+
+  QVector3D displacement () const { return m_displacement; }
+
+  void set_displacement (const QVector3D &d)
+  {
+    m_displacement = d;
+    refresh ();
+  }
+
+  double scale_factor () const { return m_scale_factor; }
+
+  void set_scale_factor (double f)
+  {
+    m_scale_factor = f;
+    refresh ();
+  }
+
+signals:
+  void scale_factor_changed (double f);
+
+protected:
+  virtual void camera_changed ();
+  virtual double aspect_ratio () const;
+
+public slots:
+  void fit ();
+
+private:
+  typedef lay::mem_chunks<GLfloat, 1024 * 18> chunks_type;
+
+  std::auto_ptr<D25InteractionMode> mp_mode;
+  QOpenGLShaderProgram *m_shapes_program, *m_gridplane_program;
+  double m_scale_factor;
+  QVector3D m_displacement;
+  lay::LayoutView *mp_view;
+  db::DBox m_bbox;
+  double m_zmin, m_zmax;
+
+  std::list<chunks_type> m_vertex_chunks;
+
+  struct LayerInfo {
+    const chunks_type *vertex_chunk;
+    GLfloat color [4];
+  };
+
+  std::list<LayerInfo> m_layers;
+
+  void initializeGL ();
+  void paintGL ();
+  void resizeGL (int w, int h);
+
+  bool prepare_view();
+  void render_layout (D25ViewWidget::chunks_type &chunks, const db::Layout &layout, const db::Cell &cell, unsigned int layer, double zstart, double zstop);
+  void render_polygon (D25ViewWidget::chunks_type &chunks, const db::Polygon &poly, double dbu, double zstart, double zstop);
+  void render_wall (D25ViewWidget::chunks_type &chunks, const db::Edge &poly, double dbu, double zstart, double zstop);
+};
+
+}
+
+#endif
+
diff --git a/src/plugins/tools/view_25d/lay_plugin/layXORPlugin.cc b/src/plugins/tools/view_25d/lay_plugin/layXORPlugin.cc
new file mode 100644
index 000000000..f5bd4895e
--- /dev/null
+++ b/src/plugins/tools/view_25d/lay_plugin/layXORPlugin.cc
@@ -0,0 +1,122 @@
+
+/*
+
+  KLayout Layout Viewer
+  Copyright (C) 2006-2020 Matthias Koefferlein
+
+  This program is free software; you can redistribute it and/or modify
+  it under the terms of the GNU General Public License as published by
+  the Free Software Foundation; either version 2 of the License, or
+  (at your option) any later version.
+
+  This program is distributed in the hope that it will be useful,
+  but WITHOUT ANY WARRANTY; without even the implied warranty of
+  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+  GNU General Public License for more details.
+
+  You should have received a copy of the GNU General Public License
+  along with this program; if not, write to the Free Software
+  Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
+
+*/
+
+
+
+#include "layXORToolDialog.h"
+#include "layDispatcher.h"
+
+#include "layPlugin.h"
+
+namespace lay
+{
+
+class XORPlugin
+  : public lay::Plugin
+{
+public:
+  XORPlugin (Plugin *parent, lay::LayoutView *view)
+    : lay::Plugin (parent), mp_view (view)
+  {
+    mp_dialog = new lay::XORToolDialog (0);
+  }
+
+  ~XORPlugin ()
+  {
+    delete mp_dialog;
+    mp_dialog = 0;
+  }
+
+  void menu_activated (const std::string &symbol) 
+  {
+    if (symbol == "lay::xor_tool") {
+
+      if (mp_dialog->exec_dialog (mp_view)) {
+
+        // ... implementation is in layXORToolDialog.cc ...
+
+      }
+
+    }
+  }
+
+private:
+  lay::LayoutView *mp_view;
+  lay::XORToolDialog *mp_dialog;
+};
+
+class XORPluginDeclaration
+  : public lay::PluginDeclaration
+{
+public:
+  XORPluginDeclaration ()
+  {
+    //  .. nothing yet ..
+  }
+  
+  virtual void get_options (std::vector < std::pair<std::string, std::string> > &options) const
+  {
+    options.push_back (std::pair<std::string, std::string> (cfg_xor_input_mode, "all"));
+    options.push_back (std::pair<std::string, std::string> (cfg_xor_output_mode, "rdb"));
+    options.push_back (std::pair<std::string, std::string> (cfg_xor_nworkers, "1"));
+    options.push_back (std::pair<std::string, std::string> (cfg_xor_layer_offset, ""));
+    options.push_back (std::pair<std::string, std::string> (cfg_xor_axorb, "true"));
+    options.push_back (std::pair<std::string, std::string> (cfg_xor_anotb, "false"));
+    options.push_back (std::pair<std::string, std::string> (cfg_xor_bnota, "false"));
+    options.push_back (std::pair<std::string, std::string> (cfg_xor_summarize, "false"));
+    options.push_back (std::pair<std::string, std::string> (cfg_xor_tolerances, ""));
+    options.push_back (std::pair<std::string, std::string> (cfg_xor_tiling, ""));
+    options.push_back (std::pair<std::string, std::string> (cfg_xor_region_mode, "all"));
+  }
+
+  virtual lay::ConfigPage *config_page (QWidget * /*parent*/, std::string & /*title*/) const
+  {
+    // .. nothing yet ..
+    return 0;
+  }
+
+  virtual void get_menu_entries (std::vector<lay::MenuEntry> &menu_entries) const
+  {
+    lay::PluginDeclaration::get_menu_entries (menu_entries);
+    menu_entries.push_back (lay::menu_item ("lay::xor_tool", "xor_tool:edit", "tools_menu.post_verification_group", tl::to_string (QObject::tr ("XOR Tool"))));
+  }
+
+  virtual bool configure (const std::string & /*name*/, const std::string & /*value*/)
+  {
+    return false;
+  }
+
+  virtual void config_finalize ()
+  {
+    // .. nothing yet ..
+  }
+
+  lay::Plugin *create_plugin (db::Manager *, lay::Dispatcher *root, lay::LayoutView *view) const
+  {
+    return new XORPlugin (root, view);
+  }
+};
+
+static tl::RegisteredClass<lay::PluginDeclaration> config_decl (new lay::XORPluginDeclaration (), 3000, "lay::XORPlugin");
+
+}
+
diff --git a/src/plugins/tools/view_25d/lay_plugin/lay_plugin.pro b/src/plugins/tools/view_25d/lay_plugin/lay_plugin.pro
new file mode 100644
index 000000000..2ef786e9b
--- /dev/null
+++ b/src/plugins/tools/view_25d/lay_plugin/lay_plugin.pro
@@ -0,0 +1,27 @@
+
+TARGET = d25_ui
+DESTDIR = $$OUT_PWD/../../../../lay_plugins
+
+include($$PWD/../../../lay_plugin.pri)
+
+INCLUDEPATH += $$RDB_INC $$ANT_INC
+DEPENDPATH += $$RDB_INC $$ANT_INC
+LIBS += -L$$DESTDIR/.. -lklayout_rdb -lklayout_ant
+
+HEADERS = \
+  layD25View.h \
+  layD25ViewWidget.h \
+    layD25MemChunks.h \
+    layD25ViewUtils.h \
+    layD25Camera.h
+
+SOURCES = \
+  layD25View.cc \
+  layD25ViewWidget.cc \
+  layD25Plugin.cc \
+    layD25MemChunks.cc \
+    layD25ViewUtils.cc \
+    layD25Camera.cc
+
+FORMS = \
+  D25View.ui \
diff --git a/src/plugins/tools/view_25d/unit_tests/layD25CameraTests.cc b/src/plugins/tools/view_25d/unit_tests/layD25CameraTests.cc
new file mode 100644
index 000000000..2934a9a9c
--- /dev/null
+++ b/src/plugins/tools/view_25d/unit_tests/layD25CameraTests.cc
@@ -0,0 +1,102 @@
+
+/*
+
+  KLayout Layout Viewer
+  Copyright (C) 2006-2020 Matthias Koefferlein
+
+  This program is free software; you can redistribute it and/or modify
+  it under the terms of the GNU General Public License as published by
+  the Free Software Foundation; either version 2 of the License, or
+  (at your option) any later version.
+
+  This program is distributed in the hope that it will be useful,
+  but WITHOUT ANY WARRANTY; without even the implied warranty of
+  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+  GNU General Public License for more details.
+
+  You should have received a copy of the GNU General Public License
+  along with this program; if not, write to the Free Software
+  Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
+
+*/
+
+
+#include "layD25Camera.h"
+#include "tlUnitTest.h"
+
+static std::string v2s (const QVector4D &v)
+{
+  return tl::to_string (v.x ()) + "," + tl::to_string (v.y ()) + "," + tl::to_string (v.z ());
+}
+
+static std::string v2s (const QVector3D &v)
+{
+  return tl::to_string (v.x ()) + "," + tl::to_string (v.y ()) + "," + tl::to_string (v.z ());
+}
+
+static std::string v2s_2d (const QVector3D &v)
+{
+  return tl::to_string (v.x ()) + "," + tl::to_string (v.y ());
+}
+
+TEST(1_Transformations)
+{
+  lay::D25Camera cam;
+
+  cam.set_cam_azimuth (45.0);
+  EXPECT_EQ (cam.cam_azimuth (), 45.0);
+  cam.set_cam_elevation (22.0);
+  EXPECT_EQ (cam.cam_elevation (), 22.0);
+
+  cam.camera_reset ();
+  EXPECT_EQ (cam.cam_azimuth (), 0.0);
+  EXPECT_EQ (cam.cam_elevation (), 0.0);
+
+  EXPECT_EQ (v2s (cam.cam_trans ().map (QVector4D (1, 0, 0, 1))), "1,0,0");
+  EXPECT_EQ (v2s (cam.cam_trans ().map (QVector4D (0, 1, 0, 1))), "0,1,0");
+  EXPECT_EQ (v2s (cam.cam_trans ().map (QVector4D (0, 0, 1, 1))), "0,0,1");
+  EXPECT_EQ (v2s (cam.cam_direction ()), "0,0,-1");
+  EXPECT_EQ (v2s (cam.cam_position ()), "0,0,4");
+
+  //  looking up from the bottom, x axis stays the same (azimuth = 0)
+  cam.set_cam_elevation (90.0);
+
+  EXPECT_EQ (v2s (cam.cam_trans ().map (QVector4D (1, 0, 0, 1))), "1,0,0");
+  EXPECT_EQ (v2s (cam.cam_trans ().map (QVector4D (0, 1, 0, 1))), "0,0,-1");
+  EXPECT_EQ (v2s (cam.cam_trans ().map (QVector4D (0, 0, 1, 1))), "0,1,0");
+
+  EXPECT_EQ (v2s (cam.cam_direction ()), "0,1,0");
+  EXPECT_EQ (v2s (cam.cam_position ()), "0,-4,0");
+
+  //  looking down from the top, x axis stays the same (azimuth = 0)
+  cam.set_cam_elevation (-90.0);
+
+  EXPECT_EQ (v2s (cam.cam_trans ().map (QVector4D (1, 0, 0, 1))), "1,0,0");
+  EXPECT_EQ (v2s (cam.cam_trans ().map (QVector4D (0, 1, 0, 1))), "0,0,1");
+  EXPECT_EQ (v2s (cam.cam_trans ().map (QVector4D (0, 0, 1, 1))), "0,-1,0");
+
+  EXPECT_EQ (v2s (cam.cam_direction ()), "0,-1,0");
+  EXPECT_EQ (v2s (cam.cam_position ()), "0,4,0");
+
+  //  looking from the left, y axis stays the same (elevation = 0)
+  cam.set_cam_elevation (0.0);
+  cam.set_cam_azimuth (90.0);
+
+  EXPECT_EQ (v2s (cam.cam_trans ().map (QVector4D (1, 0, 0, 1))), "0,0,-1");
+  EXPECT_EQ (v2s (cam.cam_trans ().map (QVector4D (0, 1, 0, 1))), "0,1,0");
+  EXPECT_EQ (v2s (cam.cam_trans ().map (QVector4D (0, 0, 1, 1))), "1,0,0");
+
+  EXPECT_EQ (v2s (cam.cam_direction ()), "1,0,0");
+  EXPECT_EQ (v2s (cam.cam_position ()), "-4,0,0");
+
+  //  looking from the right, y axis stays the same (elevation = 0)
+  cam.set_cam_elevation (0.0);
+  cam.set_cam_azimuth (-90.0);
+
+  EXPECT_EQ (v2s (cam.cam_trans ().map (QVector4D (1, 0, 0, 1))), "0,0,1");
+  EXPECT_EQ (v2s (cam.cam_trans ().map (QVector4D (0, 1, 0, 1))), "0,1,0");
+  EXPECT_EQ (v2s (cam.cam_trans ().map (QVector4D (0, 0, 1, 1))), "-1,0,0");
+
+  EXPECT_EQ (v2s (cam.cam_direction ()), "-1,0,0");
+  EXPECT_EQ (v2s (cam.cam_position ()), "4,0,0");
+}
diff --git a/src/plugins/tools/view_25d/unit_tests/layD25MemChunksTests.cc b/src/plugins/tools/view_25d/unit_tests/layD25MemChunksTests.cc
new file mode 100644
index 000000000..5482762a0
--- /dev/null
+++ b/src/plugins/tools/view_25d/unit_tests/layD25MemChunksTests.cc
@@ -0,0 +1,90 @@
+
+/*
+
+  KLayout Layout Viewer
+  Copyright (C) 2006-2020 Matthias Koefferlein
+
+  This program is free software; you can redistribute it and/or modify
+  it under the terms of the GNU General Public License as published by
+  the Free Software Foundation; either version 2 of the License, or
+  (at your option) any later version.
+
+  This program is distributed in the hope that it will be useful,
+  but WITHOUT ANY WARRANTY; without even the implied warranty of
+  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+  GNU General Public License for more details.
+
+  You should have received a copy of the GNU General Public License
+  along with this program; if not, write to the Free Software
+  Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
+
+*/
+
+
+#include "layD25MemChunks.h"
+#include "tlUnitTest.h"
+
+TEST(1_Basic)
+{
+  lay::mem_chunks<int, 2> ch;
+  EXPECT_EQ (ch.begin () == ch.end (), true);
+
+  ch.add (1);
+  EXPECT_EQ (ch.begin () == ch.end (), false);
+  EXPECT_EQ (ch.begin ()->size (), size_t (1));
+  EXPECT_EQ (ch.begin ()->front () [0], 1);
+
+  ch.add (17);
+  EXPECT_EQ (ch.begin () == ch.end (), false);
+  EXPECT_EQ (ch.begin ()->size (), size_t (2));
+  EXPECT_EQ (ch.begin ()->front () [0], 1);
+  EXPECT_EQ (ch.begin ()->front () [1], 17);
+
+  lay::mem_chunks<int, 2>::iterator c = ch.begin ();
+  EXPECT_EQ (c == ch.end (), false);
+  ++c;
+  EXPECT_EQ (c == ch.end (), true);
+
+  ch.add (42);
+  c = ch.begin ();
+  EXPECT_EQ (c == ch.end (), false);
+  EXPECT_EQ (c->size (), size_t (2));
+  EXPECT_EQ (c->front () [0], 1);
+  EXPECT_EQ (c->front () [1], 17);
+  ++c;
+  EXPECT_EQ (c == ch.end (), false);
+  EXPECT_EQ (c->size (), size_t (1));
+  EXPECT_EQ (c->front () [0], 42);
+  ++c;
+  EXPECT_EQ (c == ch.end (), true);
+
+  ch.clear ();
+  EXPECT_EQ (ch.begin () == ch.end (), true);
+}
+
+TEST(2_Copy)
+{
+  lay::mem_chunks<int, 2> ch1;
+  ch1.add (1);
+  ch1.add (17);
+  ch1.add (42);
+
+  lay::mem_chunks<int, 2> ch (ch1);
+
+  lay::mem_chunks<int, 2>::iterator c = ch.begin ();
+
+  EXPECT_EQ (c == ch.end (), false);
+  EXPECT_EQ (c->size (), size_t (2));
+  EXPECT_EQ (c->front () [0], 1);
+  EXPECT_EQ (c->front () [1], 17);
+  ++c;
+  EXPECT_EQ (c == ch.end (), false);
+  EXPECT_EQ (c->size (), size_t (1));
+  EXPECT_EQ (c->front () [0], 42);
+  ++c;
+  EXPECT_EQ (c == ch.end (), true);
+
+  ch1.clear ();
+  ch = ch1;
+  EXPECT_EQ (ch.begin () == ch.end (), true);
+}
diff --git a/src/plugins/tools/view_25d/unit_tests/layD25ViewUtilsTests.cc b/src/plugins/tools/view_25d/unit_tests/layD25ViewUtilsTests.cc
new file mode 100644
index 000000000..4e428c818
--- /dev/null
+++ b/src/plugins/tools/view_25d/unit_tests/layD25ViewUtilsTests.cc
@@ -0,0 +1,240 @@
+
+/*
+
+  KLayout Layout Viewer
+  Copyright (C) 2006-2020 Matthias Koefferlein
+
+  This program is free software; you can redistribute it and/or modify
+  it under the terms of the GNU General Public License as published by
+  the Free Software Foundation; either version 2 of the License, or
+  (at your option) any later version.
+
+  This program is distributed in the hope that it will be useful,
+  but WITHOUT ANY WARRANTY; without even the implied warranty of
+  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+  GNU General Public License for more details.
+
+  You should have received a copy of the GNU General Public License
+  along with this program; if not, write to the Free Software
+  Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
+
+*/
+
+
+#include "layD25ViewUtils.h"
+#include "tlUnitTest.h"
+
+static std::string v2s (const QVector3D &v)
+{
+  return tl::to_string (v.x ()) + "," + tl::to_string (v.y ()) + "," + tl::to_string (v.z ());
+}
+
+static std::string v2s_2d (const QVector3D &v)
+{
+  return tl::to_string (v.x ()) + "," + tl::to_string (v.y ());
+}
+
+TEST(1_CutPoint)
+{
+  std::pair<bool, QVector3D> r;
+
+  r = lay::cutpoint_line_with_plane (QVector3D (0, 0, 0), QVector3D (0, 0, 1), QVector3D (0, 0, 0), QVector3D (1, 0, 0));
+  EXPECT_EQ (r.first, false);
+
+  r = lay::cutpoint_line_with_plane (QVector3D (1, 2, 3), QVector3D (0, 0, 2), QVector3D (4, 5, 6), QVector3D (0, 0, 1));
+  EXPECT_EQ (r.first, true);
+  EXPECT_EQ (v2s (r.second), "1,2,6");
+
+  r = lay::cutpoint_line_with_plane (QVector3D (1, 2, 3), QVector3D (0, 0, -1), QVector3D (4, 5, 6), QVector3D (1, 1, 1));
+  EXPECT_EQ (r.first, true);
+  EXPECT_EQ (v2s (r.second), "1,2,12");
+}
+
+TEST(2_Face)
+{
+  std::pair<bool, QVector3D> r;
+
+  r = lay::cutpoint_line_with_face (QVector3D (0, 0, 0), QVector3D (0, 0, 1), QVector3D (0, 0, 0), QVector3D (0, 1, 0), QVector3D (0, 0, 1));
+  EXPECT_EQ (r.first, false);
+
+  r = lay::cutpoint_line_with_face (QVector3D (1, 2, 3), QVector3D (0, 0, 2), QVector3D (4, 5, 6), QVector3D (0, 1, 0), QVector3D (1, 0, 0));
+  EXPECT_EQ (r.first, false);
+
+  r = lay::cutpoint_line_with_face (QVector3D (4, 5, 3), QVector3D (0, 0, 3), QVector3D (4, 5, 6), QVector3D (0, 1, 0), QVector3D (1, 0, 0));
+  EXPECT_EQ (r.first, true);
+  EXPECT_EQ (v2s (r.second), "4,5,6");
+
+  r = lay::cutpoint_line_with_face (QVector3D (4, 7, 3), QVector3D (0, 0, 1), QVector3D (4, 5, 6), QVector3D (0, 1, 0), QVector3D (1, 0, 0));
+  EXPECT_EQ (r.first, false);
+
+  r = lay::cutpoint_line_with_face (QVector3D (4, 6, 3), QVector3D (0, 0, 2), QVector3D (4, 5, 6), QVector3D (0, 1, 0), QVector3D (1, 0, 0));
+  EXPECT_EQ (r.first, true);
+  EXPECT_EQ (v2s (r.second), "4,6,6");
+
+  r = lay::cutpoint_line_with_face (QVector3D (5, 6, 3), QVector3D (0, 0, -1), QVector3D (4, 5, 6), QVector3D (0, 1, 0), QVector3D (1, 0, 0));
+  EXPECT_EQ (r.first, true);
+  EXPECT_EQ (v2s (r.second), "5,6,6");
+
+  r = lay::cutpoint_line_with_face (QVector3D (6, 6, 3), QVector3D (0, 0, 1), QVector3D (4, 5, 6), QVector3D (0, 1, 0), QVector3D (1, 0, 0));
+  EXPECT_EQ (r.first, false);
+}
+
+TEST(3_HitWithCuboid)
+{
+  std::pair<bool, QVector3D> r;
+
+  r = lay::hit_point_with_cuboid (QVector3D (0, 0, 0), QVector3D (0, 0, 1), QVector3D (-1, -1, 3), QVector3D (2, 2, 2));
+  EXPECT_EQ (r.first, true);
+  EXPECT_EQ (v2s (r.second), "0,0,3");
+
+  r = lay::hit_point_with_cuboid (QVector3D (1, 1, 4), QVector3D (0, 0, 1), QVector3D (-1, -1, 3), QVector3D (2, 2, 2));
+  EXPECT_EQ (r.first, true);
+  EXPECT_EQ (v2s (r.second), "1,1,4");
+
+  r = lay::hit_point_with_cuboid (QVector3D (1, 1, 6), QVector3D (0, 0, 1), QVector3D (-1, -1, 3), QVector3D (2, 2, 2));
+  EXPECT_EQ (r.first, true);
+  EXPECT_EQ (v2s (r.second), "1,1,3");
+
+  r = lay::hit_point_with_cuboid (QVector3D (5, -6, 0), QVector3D (0, 0, 1), QVector3D (-1, -1, 3), QVector3D (2, 2, 2));
+  EXPECT_EQ (r.first, true);
+  EXPECT_EQ (v2s (r.second), "5,-6,3");
+
+  r = lay::hit_point_with_cuboid (QVector3D (5, -6, 4), QVector3D (0, 0, 1), QVector3D (-1, -1, 3), QVector3D (2, 2, 2));
+  EXPECT_EQ (r.first, true);
+  EXPECT_EQ (v2s (r.second), "5,-6,3");
+
+  r = lay::hit_point_with_cuboid (QVector3D (5, -6, 6), QVector3D (0, 0, 1), QVector3D (-1, -1, 3), QVector3D (2, 2, 2));
+  EXPECT_EQ (r.first, true);
+  EXPECT_EQ (v2s (r.second), "5,-6,3");
+
+  r = lay::hit_point_with_cuboid (QVector3D (5, 0, 0), QVector3D (-1, 0, 0), QVector3D (-1, -1, 3), QVector3D (2, 2, 2));
+  EXPECT_EQ (r.first, true);
+  EXPECT_EQ (v2s (r.second), "1,0,0");
+
+  r = lay::hit_point_with_cuboid (QVector3D (-5, 0, 0), QVector3D (1, 0, 0), QVector3D (-1, -1, 3), QVector3D (2, 2, 2));
+  EXPECT_EQ (r.first, true);
+  EXPECT_EQ (v2s (r.second), "-1,0,0");
+}
+
+TEST(4_CameraNormal)
+{
+  QMatrix4x4 matrix;
+  matrix.perspective (60.0f, 1.5, 0.1f, 100.0f);
+
+  std::pair<QVector3D, QVector3D> ray;
+  QVector3D p;
+
+  ray = lay::camera_normal (matrix, 0.0, 0.0);
+  EXPECT_EQ (v2s (ray.second.normalized ()), "0,0,-1");
+
+  ray = lay::camera_normal (matrix, 1.0, 0.0);
+  EXPECT_EQ (v2s (ray.second), "0.654654,0,-0.755929");
+
+  p = matrix.map (ray.first);
+  EXPECT_EQ (v2s_2d (p), "1,0");
+
+  p = matrix.map (ray.first + ray.second);
+  EXPECT_EQ (v2s_2d (p), "1,0");
+
+  p = matrix.map (ray.first + ray.second * 1000.0);
+  EXPECT_EQ (v2s_2d (p), "1,0");
+
+  ray = lay::camera_normal (matrix, 0.0, -1.0);
+  EXPECT_EQ (v2s (ray.second), "0,-0.5,-0.866025");
+
+  p = matrix.map (ray.first);
+  EXPECT_EQ (v2s_2d (p), "0,-1");
+
+  p = matrix.map (ray.first + ray.second);
+  EXPECT_EQ (v2s_2d (p), "0,-1");
+
+  p = matrix.map (ray.first + ray.second * 1000.0);
+  EXPECT_EQ (v2s_2d (p), "0,-1");
+}
+
+TEST(5_CameraNormal)
+{
+  QMatrix4x4 matrix;
+  QVector3D p;
+
+  matrix.perspective (60.0f, 1.5, 0.1f, 100.0f);
+  matrix.rotate (22.0, 1.0, 0.0, 0.0);
+  matrix.rotate (-15.0, 0.0, 1.0, 0.0);
+  matrix.translate (QVector3D (0.0, 0.0, 4.0));
+
+  std::pair<QVector3D, QVector3D> ray;
+
+  ray = lay::camera_normal (matrix, 0.0, 1.0);
+  EXPECT_EQ (v2s (ray.second), "-0.2563,0.139173,-0.956526");
+
+  p = matrix.map (ray.first);
+  EXPECT_EQ (v2s_2d (p), "0,1");
+
+  p = matrix.map (ray.first + ray.second);
+  EXPECT_EQ (v2s_2d (p), "0,1");
+
+  p = matrix.map (ray.first + ray.second * 1000.0);
+  EXPECT_EQ (v2s_2d (p), "0,1");
+}
+
+TEST(6_NormalizeSceneTrans)
+{
+  QMatrix4x4 cam;
+  cam.perspective (60.0f, 1.5, 0.1f, 100.0f);
+  cam.rotate (22.0, 1.0, 0.0, 0.0);
+  cam.rotate (-15.0, 0.0, 1.0, 0.0);
+  cam.translate (QVector3D (0.0, 0.0, 4.0));
+
+  double scale = 0.1;
+  QVector3D displacement (-5.0, 2.0, 20.0);
+
+  QMatrix4x4 scene1;
+  scene1.scale (scale);
+  scene1.translate (displacement);
+
+  QVector3D v1 = (cam * scene1).map (QVector3D (1.0, -1.0, 2.0));
+  v1.setZ (0);
+  QVector3D v2 = (cam * scene1).map (QVector3D (0.0, 0.0, 5.0));
+  v2.setZ (0);
+  QVector3D v3 = (cam * scene1).map (QVector3D (-1.0, 0.0, 1.0));
+  v3.setZ (0);
+
+  lay::normalize_scene_trans (cam, displacement, scale);
+
+  QMatrix4x4 scene2;
+  scene2.scale (scale);
+  scene2.translate (displacement);
+
+  EXPECT_EQ (tl::sprintf ("%.4f", scale), "0.0667");
+
+  QVector3D u1 = (cam * scene2).map (QVector3D (1.0, -1.0, 2.0));
+  u1.setZ (0);
+  QVector3D u2 = (cam * scene2).map (QVector3D (0.0, 0.0, 5.0));
+  u2.setZ (0);
+  QVector3D u3 = (cam * scene2).map (QVector3D (-1.0, 0.0, 1.0));
+  u3.setZ (0);
+
+  EXPECT_EQ ((u1 - v1).length () < 1e-4, true);
+  EXPECT_EQ ((u2 - v2).length () < 1e-4, true);
+  EXPECT_EQ ((u3 - v3).length () < 1e-4, true);
+
+  lay::normalize_scene_trans (cam, displacement, scale, 10.0);
+
+  QMatrix4x4 scene3;
+  scene3.scale (scale);
+  scene3.translate (displacement);
+
+  EXPECT_EQ (tl::sprintf ("%.4f", scale), "0.0800");
+  EXPECT_EQ (tl::to_string (displacement.z ()), "10");
+
+  QVector3D uu1 = (cam * scene2).map (QVector3D (1.0, -1.0, 2.0));
+  uu1.setZ (0);
+  QVector3D uu2 = (cam * scene2).map (QVector3D (0.0, 0.0, 5.0));
+  uu2.setZ (0);
+  QVector3D uu3 = (cam * scene2).map (QVector3D (-1.0, 0.0, 1.0));
+  uu3.setZ (0);
+
+  EXPECT_EQ ((uu1 - v1).length () < 1e-4, true);
+  EXPECT_EQ ((uu2 - v2).length () < 1e-4, true);
+  EXPECT_EQ ((uu3 - v3).length () < 1e-4, true);
+}
diff --git a/src/plugins/tools/view_25d/unit_tests/unit_tests.pro b/src/plugins/tools/view_25d/unit_tests/unit_tests.pro
new file mode 100644
index 000000000..c3e4e8e21
--- /dev/null
+++ b/src/plugins/tools/view_25d/unit_tests/unit_tests.pro
@@ -0,0 +1,21 @@
+
+DESTDIR_UT = $$OUT_PWD/../../../..
+
+TARGET = view_25d_tests
+
+include($$PWD/../../../../lib_ut.pri)
+
+SOURCES = \
+  layD25MemChunksTests.cc \
+    layD25ViewUtilsTests.cc \
+    layD25CameraTests.cc
+
+INCLUDEPATH += $$LAY_INC $$TL_INC $$DB_INC $$GSI_INC $$PWD/../lay_plugin $$PWD/../../../common
+DEPENDPATH += $$LAY_INC $$TL_INC $$DB_INC $$GSI_INC $$PWD/../lay_plugin $$PWD/../../../common
+
+LIBS += -L$$DESTDIR_UT -lklayout_db -lklayout_tl -lklayout_gsi
+
+PLUGINPATH = $$OUT_PWD/../../../../lay_plugins
+QMAKE_RPATHDIR += $$PLUGINPATH
+
+LIBS += -L$$PLUGINPATH -ld25_ui
diff --git a/src/plugins/tools/view_25d/view_25d.pro b/src/plugins/tools/view_25d/view_25d.pro
new file mode 100644
index 000000000..30278d0c8
--- /dev/null
+++ b/src/plugins/tools/view_25d/view_25d.pro
@@ -0,0 +1,6 @@
+
+TEMPLATE = subdirs
+
+equals(HAVE_QT5, "1") {
+  SUBDIRS = lay_plugin unit_tests
+}
diff --git a/src/tl/tl.pro b/src/tl/tl.pro
index 841b38262..b85db09a0 100644
--- a/src/tl/tl.pro
+++ b/src/tl/tl.pro
@@ -1,6 +1,9 @@
 
 TEMPLATE = subdirs
 SUBDIRS = tl unit_tests
+*bsd* {
+    LIBS += -lexecinfo
+}
 
 unit_tests.depends += tl
 
diff --git a/src/tl/tl/tlFileUtils.cc b/src/tl/tl/tlFileUtils.cc
index b608139c4..7a8078883 100644
--- a/src/tl/tl/tlFileUtils.cc
+++ b/src/tl/tl/tlFileUtils.cc
@@ -59,6 +59,13 @@
 
 #endif
 
+#if defined(__FreeBSD__)
+
+#include <sys/types.h>
+#include <sys/sysctl.h>
+
+#endif
+
 namespace tl
 {
 
@@ -816,6 +823,16 @@ get_inst_path_internal ()
     return tl::absolute_path (buffer);
   }
 
+#elif defined (__FreeBSD__)
+
+  char path[PATH_MAX];
+  size_t len = PATH_MAX;
+  const int mib[4] = {CTL_KERN, KERN_PROC, KERN_PROC_PATHNAME, -1};
+  if (sysctl(&mib[0], 4, &path, &len, NULL, 0) == 0) {
+    return tl::absolute_path(path);
+  }
+  return "";
+
 #else
 
   std::string pf = tl::sprintf ("/proc/%d/exe", getpid ());
diff --git a/src/tl/tl/tlIntervalMap.h b/src/tl/tl/tlIntervalMap.h
index edfb819d9..0f84b29b9 100644
--- a/src/tl/tl/tlIntervalMap.h
+++ b/src/tl/tl/tlIntervalMap.h
@@ -270,6 +270,23 @@ public:
     }
   }
 
+  /**
+   *  @brief Returns the iterator for a given index
+   *
+   *  This will return the iterator for the interval which contains the index. If there is no such interval, this method
+   *  will return end().
+   *
+   *  If there is no interval for the given index (not set), the returned iterator will not be end(), but it's
+   *  start value will not be less or equal to the index.
+   *
+   *  @param i The index to search for
+   *  @return The iterator to the corresponding interval or end() if there is no such interval
+   */
+  const_iterator find (I i) const
+  {
+    return std::lower_bound (m_index_map.begin (), m_index_map.end (), i, iv_compare_f<I, T> ());
+  }
+
   /**
    *  @brief Do a brief check if the structure is sorted
    */
diff --git a/src/tl/tl/tlStream.cc b/src/tl/tl/tlStream.cc
index 753e5e16b..36f6a8b3c 100644
--- a/src/tl/tl/tlStream.cc
+++ b/src/tl/tl/tlStream.cc
@@ -32,6 +32,8 @@
 #include <zlib.h>
 #ifdef _WIN32 
 #  include <io.h>
+#else
+#  include <unistd.h>
 #endif
 
 #include "tlStream.h"
diff --git a/testdata/algo/device_extract_au13_circuits.gds b/testdata/algo/device_extract_au13_circuits.gds
new file mode 100644
index 000000000..131540011
Binary files /dev/null and b/testdata/algo/device_extract_au13_circuits.gds differ
diff --git a/testdata/algo/device_extract_l13.gds b/testdata/algo/device_extract_l13.gds
new file mode 100644
index 000000000..2fad35e6b
Binary files /dev/null and b/testdata/algo/device_extract_l13.gds differ
diff --git a/testdata/algo/nreader9.cir b/testdata/algo/nreader9.cir
index 302b7a0a2..e68e4bd20 100644
--- a/testdata/algo/nreader9.cir
+++ b/testdata/algo/nreader9.cir
@@ -1,10 +1,18 @@
 
 R$1 1 2 1.7k M=2
 R$2 3 4 1.7k
+R$3 1 2 1.7k RMODEL M=2
+R$4 3 4 1.7k RMODEL
 M$1 1 2 3 4 NMOS W=2u L=7u M=2
 M$2 1 2 3 4 PMOS W=2u L=7u 
 C$1 1 2 1e-9 M=2 
 C$2 3 4 1e-9 
+C$3 1 2 1e-9 CMODEL M=2 
+C$4 3 4 1e-9 CMODEL 
+L$1 1 2 1e-9 M=2 
+L$2 3 4 1e-9 
+L$3 1 2 1e-9 LMODEL M=2 
+L$4 3 4 1e-9 LMODEL 
 D$1 1 2 DIODE A=10P M=2 
 D$2 3 4 DIODE A=10P
 Q$1 1 2 3 4 BIP AE=10P M=2 
diff --git a/testdata/drc/drcSimpleTests_17.drc b/testdata/drc/drcSimpleTests_17.drc
new file mode 100644
index 000000000..8cdbc5992
--- /dev/null
+++ b/testdata/drc/drcSimpleTests_17.drc
@@ -0,0 +1,42 @@
+
+source($drc_test_source)
+in_cell     = source.select("-", "+S*")
+not_in_cell = source.select("-SPECIAL")
+in_cell_local = source.select("-*", "+SPECIAL")
+not_in_cell_local = source.select("+*", "-SPECIAL")
+
+target($drc_test_target)
+
+deep 
+
+input(2,0).output(2, 0)
+input(3,0).output(3, 0)
+
+flat
+
+in_cell.input(2, 0).output(102, 0)
+in_cell.input(3, 0).output(103, 0)
+
+not_in_cell.input(2, 0).output(202, 0)
+not_in_cell.input(3, 0).output(203, 0)
+
+in_cell_local.input(2, 0).output(302, 0)
+in_cell_local.input(3, 0).output(303, 0)
+
+not_in_cell_local.input(2, 0).output(402, 0)
+not_in_cell_local.input(3, 0).output(403, 0)
+
+deep 
+
+in_cell.input(2, 0).output(502, 0)
+in_cell.input(3, 0).output(503, 0)
+
+not_in_cell.input(2, 0).output(602, 0)
+not_in_cell.input(3, 0).output(603, 0)
+
+in_cell_local.input(2, 0).output(702, 0)
+in_cell_local.input(3, 0).output(703, 0)
+
+not_in_cell_local.input(2, 0).output(802, 0)
+not_in_cell_local.input(3, 0).output(803, 0)
+
diff --git a/testdata/drc/drcSimpleTests_17.gds b/testdata/drc/drcSimpleTests_17.gds
new file mode 100644
index 000000000..0718d5171
Binary files /dev/null and b/testdata/drc/drcSimpleTests_17.gds differ
diff --git a/testdata/drc/drcSimpleTests_au17.gds b/testdata/drc/drcSimpleTests_au17.gds
new file mode 100644
index 000000000..ceeb45db2
Binary files /dev/null and b/testdata/drc/drcSimpleTests_au17.gds differ
diff --git a/testdata/gds/collect_add_au.gds b/testdata/gds/collect_add_au.gds
new file mode 100644
index 000000000..ca0206610
Binary files /dev/null and b/testdata/gds/collect_add_au.gds differ
diff --git a/testdata/gds/collect_added.gds b/testdata/gds/collect_added.gds
new file mode 100644
index 000000000..e4882b6d8
Binary files /dev/null and b/testdata/gds/collect_added.gds differ
diff --git a/testdata/gds/collect_basic.gds b/testdata/gds/collect_basic.gds
new file mode 100644
index 000000000..9fad7517e
Binary files /dev/null and b/testdata/gds/collect_basic.gds differ
diff --git a/testdata/gds/collect_overwrite_au.gds b/testdata/gds/collect_overwrite_au.gds
new file mode 100644
index 000000000..e4790a23d
Binary files /dev/null and b/testdata/gds/collect_overwrite_au.gds differ
diff --git a/testdata/gds/collect_rename_au.gds b/testdata/gds/collect_rename_au.gds
new file mode 100644
index 000000000..af98c817f
Binary files /dev/null and b/testdata/gds/collect_rename_au.gds differ
diff --git a/testdata/gds/collect_skip_au.gds b/testdata/gds/collect_skip_au.gds
new file mode 100644
index 000000000..5a0b96fa9
Binary files /dev/null and b/testdata/gds/collect_skip_au.gds differ
diff --git a/testdata/oasis/t2.4.ot b/testdata/oasis/t2.4.ot
index 8a625c7cf..d1def8758 100644
--- a/testdata/oasis/t2.4.ot
+++ b/testdata/oasis/t2.4.ot
@@ -7,10 +7,10 @@
 #   <test-intention>Explicit assignment of ID's</test-intention>
 #   <content>
 #     begin_lib 0.001
-#     begin_cell {ABC}
-#     end_cell
 #     begin_cell {XYZ}
 #     end_cell
+#     begin_cell {ABC}
+#     end_cell
 #     end_lib
 #   </content>
 # </test>
diff --git a/testdata/oasis/t2.4_au.txt b/testdata/oasis/t2.4_au.txt
index ede7f7760..aee39fbb5 100644
--- a/testdata/oasis/t2.4_au.txt
+++ b/testdata/oasis/t2.4_au.txt
@@ -1,6 +1,6 @@
 begin_lib 0.001
-begin_cell {ABC}
-end_cell
 begin_cell {XYZ}
 end_cell
+begin_cell {ABC}
+end_cell
 end_lib
diff --git a/testdata/oasis/t2.6_au.txt b/testdata/oasis/t2.6_au.txt
index 3c0ebf770..ec8221a98 100644
--- a/testdata/oasis/t2.6_au.txt
+++ b/testdata/oasis/t2.6_au.txt
@@ -1,6 +1,6 @@
 begin_lib 0.001
-begin_cell {ABC}
-end_cell
 begin_cell { XYZ}
 end_cell
+begin_cell {ABC}
+end_cell
 end_lib
diff --git a/testdata/ruby/dbReaders.rb b/testdata/ruby/dbReaders.rb
index f96956f99..0591ade21 100644
--- a/testdata/ruby/dbReaders.rb
+++ b/testdata/ruby/dbReaders.rb
@@ -53,6 +53,14 @@ class DBReaders_TestClass < TestBase
     opt.properties_enabled = false
     assert_equal(opt.properties_enabled?, false)
 
+    assert_equal(opt.cell_conflict_resolution, RBA::LoadLayoutOptions::AddToCell)
+    opt.cell_conflict_resolution = RBA::LoadLayoutOptions::OverwriteCell
+    assert_equal(opt.cell_conflict_resolution, RBA::LoadLayoutOptions::OverwriteCell)
+    opt.cell_conflict_resolution = RBA::LoadLayoutOptions::SkipNewCell
+    assert_equal(opt.cell_conflict_resolution, RBA::LoadLayoutOptions::SkipNewCell)
+    opt.cell_conflict_resolution = RBA::LoadLayoutOptions::RenameCell
+    assert_equal(opt.cell_conflict_resolution, RBA::LoadLayoutOptions::RenameCell)
+
   end
 
   # GDS2 Options